EPA-600/7-76-009b
August 1976
MECHANISM AND KINETICS OF
THE FORMATION OF NOx
AND OTHER
COMBUSTION POLLUTANTS:
Phase II. Modified Combustion
Interagency
Energy-Environment
Research and Development
Program Report
U.S. Environmental Protection Agency
Office of Research and Development
Industrial Environmental Research
Laboratory
Research Triangle Park, N.C. 27711
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S.
Environmental Protection Agency, have been grouped into seven series.
These seven broad categories were established to facilitate further
development and application of environmental technology. Elimination
of traditional grouping was consciously planned to foster technology
transfer and a maximum interface in related fields. The seven series
are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from
the effort funded under the 17-agency Federal Energy/Environment
Research and Development Program. These studies relate to EPA's
mission to protect the public health and welfare from adverse effects
of pollutants associated with energy systems. The goal of the Program
is to assure the rapid development of domestic energy supplies in an
environmentally—compatible manner by providing the necessary
environmental data and control technology. Investigations include
analyses of the transport of energy-related pollutants and their health
and ecological effects; assessments of, and development of, control
technologies for energy systems; and integrated assessments of a wide
range of energy-related environmental issues.
REVIEW NOTICE
This report has been reviewed by the participating Federal
Agencies, and approved for publication. Approval does not
signify that the contents necessarily reflect the views and
policies of the Government, nor does mention of trade names
or commercial products constitute endorsement or recommen-
dation for use.
This document is available to the public through the National Technical
Information Service, Springfield, Virginia 22161.
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EPA-600/7-76-009b
August 1976
MECHANISM AND KINETICS
OF THE FORMATION OF NO
x
AND OTHER COMBUSTION POLLUTANTS
PHASE H. MODIFIED COMBUSTION
by
V.S. Engleman, V.J. Siminski, and W. Bartok
Exxon Research and Engineering Company
P.O. Box 8
Linden, New Jersey 07036
Contract No. 68-02-0224
ROAPNo. 21BCC-013
Program Element No. 1AB014
EPA Project Officer: W. Steven Lanier
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
-------
TABLE OF CONTENTS
Page
FOREWORD i
SUMMARY 1
1. INTRODUCTION 2
2. EXPERIMENTAL 3
3. CHEMICAL KINETICS CALCULATIONS 40
4. CONCLUSIONS AND RECOMMENDATIONS 74
Appendix A
DATA LISTINGS A_!
Appendix B
EVALUATION OF PROBABLE RELATIVE IMPORTANCE OF
REACTION STEPS FOR METHANE/AIR COMBUSTION B_!
Appendix C
SCHEMATIC OF COMBUSTION/NOx REACTIONS FOR
METHANE/AIR COMBUSTION IN STIRRED REACTOR C-l
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- i -
FOREWORD
This report summarizes the results of Phase II of a study on
the "Definition of the Mechanism and Kinetics of the Formation of N0X
and Other Pollutants under Normal and Combustion Modification Conditions".
This study was conducted by Exxon Research and Engineering Company under
Contract 68-02-0224 funded by the Environmental Protection Agency.
The helpful comments and suggestions of Mr. W. S. Lanier, the
EPA Project Officer for this contract, are gratefully acknowledged. The
skillful assistance of Mr. J. H. Ballentine was invaluable in conducting
the laboratory portion of this investigation. The consultation of
Professor H. C. Hottel was instrumental in the design of the Adiabatic
Stirred Combustor.
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- 1 -
SUMMARY
This report describes a study to relate the kinetics and
mechanisms of pollutant formation reactions and those of hydrocarbon
reactions. An understanding of the chemistry of combustion systems along
with the fluid mechanics and heat transfer of specific configurations
can lead to an understanding of the details of pollutant formation and
control.
Studies of modified combustion techniques used for N0X emission
control were studied with a flat flame burner with a controlled-temperature
post-flame zone. Normal combustion was studied with an adiabatic stirred
combustor in which fluid mechanical and heat transfer effects were minimized.
Preheat temperature and residence time were also varied in the stirred
combustor studies. Detailed probing was conducted for stable combustion
species.
The Adiabatic Stirred Combustor (ASC) is a new device, designed
to take advantage of the capability of the Multiburner (a zirconia muffle
furnace capable of achieving temperatures up to 2500 K) to operate without
heat loss from the combustion zone and the capability of a stirred reactor
to operate under chemically-controlled combustion conditions. Comparison
of the ASC data with other stirred reactor data and measurement of the
species profiles downstream of the exit plane of the stirred reactor
verified that the ASC was operating in a manner comparable to a conven-
tional jet-stirred combustor under comparable conditions and that radial
profiles were uniform.
Kinetics calculations were compared with experimental data
from the ASC to investigate the mechanism of combustion and NOx formation
under chemically-controlled conditions (i.e. not controlled by mixing or
heat transfer limitations). It was found that the calculations for
carbon monoxide and hydrogen combustion gave good matches to the
experimental results obtained with the ASC, as had been found previously
with a nonadiabatic system. In contrast to previous comparisons, where
N0X formation for hydrocarbon/air combustion in a jet-stirred combustor
could not be adequately modeled, good matches were obtained for methane/air
combustion when a more complete kinetic mechanism was used. The
calculations for methane/air combustion indicated strong interaction
between hydrocarbon species and molecular nitrogen under certain conditions.
The reaction
CH + N2 -> HCN + N
was found to dominate N atom formation under fuel rich conditions and
to be a major factor under conditions near stoichiometric air supply.
Under fuel lean conditions, the reaction
N2 + 0 -+• NO + N
was found to dominate the production of N atoms. The primary paths from
N atoms to NO are
N + OH -»• NO + H
N + 02 + NO + 0
Further study of the CH + N2 reaction as well as reactions
involved in the formation of CH and its precursors is warranted.
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- 2 -
1. INTRODUCTION
Under Contract No. 68-02-0224, sponsored by the Environmental
Protection Agency (EPA), Exxon Research and Engineering Company (Exxon),
has performed a study to relate the kinetics and mechanisms of pollutant
formation reactions and those of hydrocarbon reactions. The emphasis in
this program to date has been placed on NOx formation and destruction
reactions, as they relate to hydrocarbon combustion.
The experimental tools used previously in these studies have
been the Hultiburner unit, which can be operated with controlled rates
of heat loss and heat addition, and the Jet-Stirred Combustor, in which
transport effects are minimized and thus, chemical kinetics govern the
rates of combustion and N0X formation reactions.
In Phase I of this study, a detailed experimental investigation
was made with methane and propane fuels, using the Multiburner with premixed,
laminar diffusion, and turbulent diffusion flames, varying the mixture
ratio and heat removal rates. The flame probing data generated were
compared with kinetic analysis, based on parametric studies of the
kinetics evaluation.
During the course of this study, a critical review of the
literature on the kinetics of pollutant formation and related hydrocarbon
reactions was made for the methane/air system (1-1). Recommendations were
made on the best available rate information for each reaction.
In Phase II of this study the major objective was to investigate
the chemistry of pollutant formation in a chemically controlled system
under normal and modified combustion conditions. For this purpose, the
Adiabatic Stirred Combustor (ASC) was developed and put into use. The
ASC was designed to have two distinct zones: a stirred reactor zone,
followed by a plug flow zone. The results from the ASC experiments were
compared with detailed kinetics calculations using a pre-screened set of
reactions (see Section 3.1.3) from an evaluation of all the possible
unimolecular and bimolecular reactions for species judged to be of
potential importance in methane/air combustion. Primary attention was
focused on understanding reaction paths elucidated by this approach to
the calculations. The match of the experimental data to the calculations
was used as a guideline to determine gross inconsistencies in the mechanism.
Rate-fitting was not done merely to obtain "best-fit" curves but to assess
the sensitivity of the results to variations in kinetic parameters. Critical
reactions were singled out for further attention in independent studies.
1-1 Engleman, V. S., Survey and Evaluation of Kinetic Data on Reactions
in Methane/Air Combustion, Final Report, EPA Contract 68-02-0224,
Report No. EPA 600/2-76-003 (January 1976).
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- 3 -
2. EXPERIMENTAL
To help elucidate the mechanism of pollutant formation under
normal and modified combustion conditions, premixed flat flames and
adiabatic stirred combustor flames were studied in the Multiburner with
hot and cold walls. This section describes the experimental procedures
used in this study and presents the experimental results.
2*1 The Multiburner Furnace
The Multiburner (so-called because it was designed to burn
gaseous, liquid or solid fuels at atmospheric pressure) is an electrically
heated zirconia tube furnace capable of operating under controlled heat
loss conditions. Furnace wall temperatures of 2500°K can be obtained.
The idealized primary combustion zone in this study was of a pre-mixed
flat-flame type or a well-stirred zone followed by plug flow. In both
types of combustion, the post flame reactions are affected by the temperature
of the post-flame zones. Since the muffle tube temperature can be varied
independently of the flame conditions, a wide range of heat loss rates can be
achieved, varying from adiabatic operation to the high loss rates found in
water-wall operation. Operation under adiabatic conditions allows study
of the flame zone and post-flame zone without the additional complication
of heat transfer effects.
The furnace is shown schematically in Figure 2-1. A photograph
of the furnace is presented in Figure 2-2. The furnace heating zone has
tungsten mesh heating elements and molybdenum radiation shields and is
purged with "gettered" argon to extend furnace component lifetimes. High
temperature gasketing for the furnace is composed of zirconia felt.
Temperatures inside the furnace are monitored with unshielded tungsten-rhenium
thermocouples which also serve as the input to a proportional temperature
controller for the furnace when operating in the automatic mode. Wall
temperatures can also be monitored by optical pyrometry through three sight
ports provided in the side of the furnace. The power supply is a 25 KVA AC
unit which is also equipped with a thermal watt converter for input to the
controller in cases where it is desirable to control power input rather
than strictly the temperature of the furnace. The controller on the power
supply is also capable of operating in a "manual" mode in which case
current input to the furnace is controlled.
The muffle tube in the furnace has a heated length of
38 cm. and the "constant temperature section" of the heated zone is
uniform within +10°K under combustion operation conditions. The muffle
tube is quite stable at high temperatures and can be exposed to varying
thermal environments in the temperature range above 1600°K. However,
extreme care must be exercised in heating up and cooling down the furnace
since the zirconia is most sensitive to thermal shock in the temperature
range around 1200°K.
-------
MOLYBDENUM
RADIATION
SHIELDS
WATER-
COOLED
JACKET
TUNGSTEN
HEATING
ELEMENT
STABILIZED
ZIRCONIA
MUFFLE TUBE
-------
- 5 -
Figure 2-2
Multiburner Furnace
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- 6 -
The multiburner can operate with the combustion zone wall
temperature at any desired level and at the extremes it can either be used
to add heat to the combustion zone or, if desired, to remove heat. Thus,
the multiburner can operate with all of the flexibility of a laboratory
combustor without the high heat loss generally found in small scale
devices. This permits the use of the multiburner under combustion
conditions that would not be possible with the typical small scale combustor.
2.2 Sampling and Gas Analysis
Combustion gas samples were extracted from the reactor at various
radial and axial locations within the primary combustion zone as well as
the post flame zone. A water-cooled quartz probe, mounted on a two-degree
of_freedom, vernier-operated actuator was utilized to obtain the samples.
The interconnecting gas sampling lines were of Teflon which were heated
to 150°C to prevent water condensation. Particulate filters and water-cooled
condensers were employed at the inlet to the instrument train. Quartz and
Teflon materials of construction were used throughout the sampling system
to prevent catalytic reduction of NO by CO (2-1).
The exact position of the quartz probe within the reactor was
determined from vernier dial and linear distance indicator readings that
were located on the two-degree of freedom probe actuator.
The combustion gases were analyzed for NO and N0X with a
Thermoelectron Model 10A Chemiluminescence analyzer. The analysis for
NO was accomplished directly while the analysis for NO^ was accomplished
by converting the N02 (and under certain conditions other nitrogenous compounds)
in the stainless steel converter supplied with the instrument to NO and
then analyzing for NO.
Analyses for CO and C02 were performed with MSA 303 Analyzers
of the NDIR type. Stacked cells each with a dual range switch allowed
full-scale ranges from 0.1% to 15% for CO and from 0.5% to 25% for CO2.
Oxygen analysis was performed with a Beckman Model 742
polarographic oxygen analyzer with full scale ranges from 1% to 25%.
Hydrocarbon analyses were performed with a Beckman Model 400
flame ionization analyser with full scale ranges calibrated from 50 ppm
to 5% hydrocarbon (as methane equivalent).
2.3 Data Reduction
Experimental data were coded onto computer input forms as taken
and were reduced to measured species concentrations by a data reduction
program. The data produced in this phase of the program are presented in
Appendix A. The data were tabulated according to the type of combustion
modification studied.
2-1 Halstead, C. J. and Munro, A. J., Proceedings of the Conference on
National Gas Research and Technology, Chicago, 1971.
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- 7 -
2.4 Flat Flame Premlxed Burner Design
The water-cooled premixed flat flame burner used in this study
consisted of a fuel-air mixing chamber and a porous sintered stainless
steel grid upon which the flat flame was stabilized. The porous grid
provides a uniform velocity profile for the combustion gases entering
the furnace tube. A schematic diagram of the flat flame burner is given
in Figure 2-3.
2.5 Combustion Modifications in the
Flat Flame Burner System
Table 2-1 summarizes the various combustion modifications that
were tested in the flat flame burner system with heated and cool furnace
walls. Combustion modifications tested were staged combustion, pre-heated
air, exhaust gas recirculation, and water addition. The run numbers identify
the computer printout sheets which appear in Appendix A.
2.6 Staged Combustion
Figure 2-4 shows a schematic of the experimental setup for
studies of staged combustion. The primary air flow rate was controlled
with a needle valve and precision rotameter. CH, was metered into the
flat flame burner through a sonic orifice located immediately upstream
of the mixing chamber in order to prevent small pressure fluctuations in
the air line from affecting the fuel flow rate. A precision rotameter
and needle valve were utilized to control the secondary air flow. The
secondary air was injected radially from fifty 0.08 cm. diameter holes
into the plug flow zone at an axial location 37.5 cm. downstream of the
burner surface. The secondary air flow rate was varied from zero to 50
percent of the total (primary and secondary) air flow rate. Heated and
cold wall conditions were tested in this configuration. In the heated wall
tests, the wall temperature was varied from 1780 to 2094 K. The secondary
injection velocity was calculated to be 5.18 meters/sec. for 25% secondary
air injection and 7.92 meters/sec. for 50% secondary air injection when the
primary air flow rate was held constant at 15.84 Jl/min. The gas velocity
in the plug-flow zone at the point where the secondary air was injected
was about 3.35 meters/sec. at 1773 K.
Gas sample data were obtained at fixed axial locations of 36.75
cm. (before secondary injection) and 85.75 cm. (after secondary injection)
from the surface of the flat flame burner. All the cold wall tests (runs
333 through 336) were performed with the gas sample probe located in the
exhaust stack of the multiburner 85.75 cm. downstream from the burner.
For cold wall conditions, primary zone stoichiometry was varied from 89 to
120% stoichiometric air. Peak NOx concentrations were found to occur for
primary zone stoichiometrics close to 100% independent of the secondary air
percentage. In the cold-wall tests, the main effect of secondary injection
appeared to be simply dilution since the combustion gases had cooled
significantly by the point of secondary injection.
Table 2-2 summarizes the test conditions used during the staged
combustion runs with hot walls. Primary zone mixture ratios of 50, 60 and
80% stoichiometric air were studied. The overall mixture ratios in the
secondary zone were 50, 60, 80, 100 and 120% stoichiometric air.
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- 8 -
FIGURE 2-3
FLAT FLAME BURNER
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- 9 -
TABLE 2-1
PREMIXED FLAT FLAME COMBUSTOR
RIJN IDENTIFICATION FOR CHEMICAL
SPECIES CONCENTRATION PROFILES
CHJ Air Mixtures
Staged Combustion
Firing Rate
% Secondary
Wall Temperature
Run #
P. /m-f n._
Air
K
333
18.5
0-25
Cold
334
18.5
30-34
Cold
335
18.5
0-25
Cold
336
18.5
30-34
Cold
365
15.9
0-50
1780
369
15.9
0-50
1780
370
15.9
0-34
2094
Pre-Heated Air
Pre-Heat
Temperature
f°K^
364
15.9
298
1857
367
15.9
298
2042
368
15.9
298
1857
371
15.9
443
1985
372
15.9
443
2156
377
15.9
313-353
2224
Exhaust Gas Recirculation
Recirculation
Ratio
/volume recirculated^
>. initial volume '
374 15.9 0-0.50 1831
375 15.9 0-0.25 2027
376 15.9 0-0.10 2163
Water Addition to Reactants
Percent H^O
(volume)
378 15.9 0-2.0 2073
(a) No external heat applied to the combustor walls.
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- 10 -
FIGURE 2-4
SCHEMATIC OF FLAT FLAME BURNER SYSTEM FOR STUDIES
OF UNMODIFIED AND STAGED COMBUSTION
GAS SAMPLE
PUMP
—€—
TO ANALYTICAL TRAIN
COOLED QUARTZ SAMPLE PROBE
EXHAUST
SECONDARY AIR RING INJECTOR
PLUG
FLOW
ZONE
FLAT FLAME
BURNER
yt SONIC ORIFICE
T
0
>
>
i-
$
i-
©
:h
H.P. AIR
FUEL
H.P. AIR
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- 11 -
TABLE 2-2
CENTERLINE NO CONCENTRATIONS IN
PREMIXED FLAT-FLAME BURNER WITH
CH,/AIR AND STAGED COMBUSTION
Run
#
4-
Primary*
Primary Pet. NO
Stoich. Air (ppm)
Overall Pet.
Stoich. Air
Overall**
N0X
(ppm)
Wall
K
365
50.8 0
50.8
0***
1780
79.7
0***
1780
100.1
8
1780
369
60.1 3
60.1
2***
1780
100.1
9
1780
120.0
7
1780
370
79.2 42
79.2
38***
2094
101.7
28
2094
119.6
25
2094
*
Axial distance 37.3 cm
**
Axial distance 87.1 cm
*** Under fuel rich conditions, the number shown represents the
concentration of NO. Measurements were taken far downstream
of the flame zone and the NO2 concentrations represented only
about 5% of the total N0X in most cases.
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- 12 -
When the primary zone was maintained at 50% stoichiometric air,
no NO was found in the primary zone, and only when the overall stoichiometry
reached 100% was 8 ppm of N0X measured * With the primary zone at 60%
stoichiometric air, a small amount of NO (3 ppm) was measured in the
primary zone. However, even with secondary air injection, the increase
in N0X was not very large; N0X concentration reached 9 ppm when the overall
stoichiometry was 100% but dropped off to 7 ppm at an overall stoichiometry
of 120%, When the primary zone was maintained at 80% stoichiometric air
42 ppm of NO was formed in the primary zone. As secondary air was added,
the N0X concentration decreased by approximately the amount that would be
caused by dilution, indicating no significant increase in NOx caused by
secondary combustion.
Run No. 365, with the primary zone at 50% stoichiometric air,
illustrates the effect of secondary air injection on the plug flow zone
combustion species. The data show that with no secondary injection, the
unburned hydrocarbon concentration measured at an axial distance of
85.75 cm. was 2900 ppm. With secondary injection to bring the overall
stoichiometry to 80% and 100% the hydrocarbons decreased to 530 ppm and
7 ppm, respectively. The large change in hydrocarbons caused by secondary
injection cannot be accounted for by dilution. The low hydrocarbon and
CO concentrations resulting from secondary injection indicate that
efficient combustion was achieved.
2.7 Preheated Air and Water Addition
Figure 2-5 is a schematic diagram showing the experimental
arrangement of the multiburner furnace with the flat flame burner for
experiments conducted with preheated air and water addition studies.
The combustion air was preheated via an electrically heated stainless steel
vessel which contained ceramic spheres for increased heat transfer. The
temperature of the air was thermostatically controlled by a thermocouple
inserted into the vessel. Bypass valves were available in order that the
air heater could be eliminated from the air system when desired. As in
the unmodified combustion tests with the flat flame burner, the fuel
(CH^) and preheated air were mixed inside the burner body just prior to
their flow through the porous disc. A thermocouple located in the mixing
section provided temperature data.
Water addition to the reactants was accomplished by bubbling the
air through a pressurized, heated stainless steel vessel containing water.
The maximum amount of water added was 2% by volume of the total air plus
fuel flow (about 20% of the fuel by volume). The water concentration was
calculated from the vapor pressure of water at the known temperature and
pressure of the water vessel. Bypass valves were provided for tests that
were performed with no water addition.
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- 13 -
FIGURE 2-5
SCHEMATIC OF FLAT FLAME BURNER FOR
PREHEATED AIR AND WATER ADDITION STUDIES
GAS SAMPLE
PUMP
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- 14 -
The experimental conditions for air preheat and water addition
are shown in Table 2-1 and the data are given in Appendix A. Two levels
of preheat were selected, 298°K (representing no preheat) and 443°K. An
additional run was performed in which the preheat temperature was varied
between 313°K and 353°K. The firing rate was maintained at 15.87 l/min.
and the walls were maintained at the adiabatic flame temperature. Wall
temperature differences are illustrated by the following:
119% stoichiometric air
25"C air - 2042"K wall
170°C air - 2156°K wall
120°C air - 2073°K wall (with 2% water)
140% stoichiometric air
251,C™7iF^n!857x^~wall
170°C air - 1985°K wall
At 119% stoichiometric air, at a distance of 25 cm. from the burner face,
N0X was 83 ppm with no preheat, 190 ppm with preheat and 53 ppm with water
addition. Near the burner face (0.6 cm), however, the NOx measurements
were 22 ppm for no preheat, 16 ppm with preheat and 17 ppm with water
addition. The behavior of N0X near the burner and far downstream in the
post-flame zone bears further discussion. Near the burner, N0X is found
to be lower in the preheated case, while further downstream it is higher
in the preheated case. The Zeldovich mechanism is considered to dominate
post-flame N0X formation under fuel lean conditions. However these results,
which indicate lower N0X concentrations near the burner face with preheat
could provide support for non-Zeldovich N0X in the flame zone. More rapid
burnout of the active intermediates in the preheated case could cause a
decrease in flame zone N0X. Complete interactions between hydrocarbon
fragments, nitrogen-containing species and oxygen-containing species are
involved and possible mechanisms will be discussed in Section 3. There
was an apparent lengthening of the flame zone in the water addition case
as evidenced by the presence of hydrocarbons (>1%) at a distance of 0.1 cm
from the burner face, while none were measured without water addition.
Further investigation of these phenomena from both an experimental and
theoretical approach appears to be warranted,
2.8 Exhaust Gas Recycle
A schematic diagram of the exhaust gas recycle system
utilized with the flat flame burner/multiburner furnace is presented in
Figure 2-6. A high temperature bellows pump having a capacity of 34 l/min.
was used to withdraw the combustion gases from the multiburner exhaust
stack through a 1.27 cm. diameter probe which was located on the
centerline of the stack; facing into the exhaust stream. The pump had a
discharge pressure of 210 kPa. The combustion gases were injected into
a 1.27 cm. diameter mixing section with the primary combustion air.
The entire gas recycle system was electrically heated and thermally
insulated in order to maintain the temperature of the gases above
the dew point of the mixture. The amount of gas withdrawn through the
recycling pump was determined by measuring with NDIR analyzers the CO2
concentrations in the multiburner exhaust stack and the section where
the primary air supply was mixed with the exhaust gases. Since the total
air flow rate was known and the concentration of CO2 at both locations
was measured, the amount of gas recycled was determined.
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- 15 -
FIGURE 2-6
SCHEMATIC OF FLAT FLAME BURNER FOR EXHAUST
GAS RECYCLE STUDIES
COOLED
QUARTZ
GAS SAMPLE
PROBE
PLUG FLOW
ZONE
flat flam:
BURNER
t
GAS SAMPLE
PUMP
TO ANALYTICAL TRAIN
NDIR COg ANALYZER
EXHAUST
HEATED
-- &
INSULATED
©
©
VAC. -PRES.
PUMP
-------
- 16 -
The conditions for exhaust gas recycle are shown in Table 2-3
and the experimental data are given in Appendix A. An air leak in the
sampling system was discovered after the data were taken. While the
data in the Appendix are given as taken, the results discussed here are
corrected for the leak. Three different exhaust gas recycle rates were
evaluated; ten percent (adiabatic temperature of 2163°K), twenty-five
percent (2027°K) and fifty percent (1831°K). The firing rate in the
primary combustion zone was 15.876 1/min. and the overall mixtures were
maintained at 100 percent stoichiometric air. Additional data were taken
with no recycle at each temperature condition. (The use of 100%
stoichiometric air eliminates the need for corrections in stoichiometry
caused by residual oxygen or fuel components in the exhaust gas).
At a distance of 33.3 cm. from the burner face the NOx
concentration was 156 ppm with 10% recycle (2163°K), 60 ppm with 25%
recycle (2027°K) and 8 ppm with 50% recycle (1831°K). For comparison
with the above results, when no recycle was used by the wall temperature
was held constant, the NOx level was 237 ppm (vs. 125 ppm with 10% recycle)
with 2163°K walls, 105 ppm (vs. 60 ppm with 25% recycle) with 2027°K walls
and 74 ppm (vs. 8 ppm with 50% recycle) with 1831°K walls. The differences
noted in the NOx levels are slightly greater than would be expected from
the combined effects of decreased residence time and increased dilution
during flue gas recycle. (The corrections for dilution are shown in
Table 2-3. No correction was made for residence time.) There do not
appear to be major chemical effects caused by the recycle which are
discernible at large distances from the burner face thus the effect
appears to be primarily thermal.
2.9 Adiabatic Stirred Combustor
In Phase I of this program, a jet-stirred combustor with heat
loss to the surroundings was used. The behavior of this jet-stirred
combustor had been shown to approximate that of a well-stirred system
for N0X formation in simple non-hydrocarbon flames under kinetically
controlled conditions (2-2). However, because of the extremely strong
temperature dependence of many of the elementary reaction rates that play
a role in the formation of NOx in hydrocarbon flames, it was concluded
at the end of our Phase I studies that it would be desirable to construct
a reactor system that is capable of operation in the absence of thermal
gradients in the flame and downstream combustion gases. This would allow
comparison of theory and experimental data under even better defined conditions.
With the constraint imposed that mass diffusional gradients should be
eliminated (or at least minimized) as well, it was decided that an
adiabatic stirred reactor was needed that, if successfully developed,
could operate in the absence of both thermal and mass diffusional gradients.
This section of the present report describes the features of the adiabatic
stirred combustor (ASC) developed. Subsequent sections describe its
operation and the verification of the premise that indeed it could be
operated without significant mass and thermal gradients.
2-2 Engleman, V. S. and Bartok, W., Phase I Final Report (companion
report in this series).
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- 17 -
TABLE 2-3
EFFECT OF EXHAUST GAS RECYCLE ON NO
x
(Firing Rate 14.603 l/min.)
N0X
Run
#
% Recycle
Adiabatic
Temp. (°K)
N0X
As Measured
(PPM)
Corrected For
EGR Dilution
(PPM)
376
0
2163
237
237
376
10
2163
156
173
375
0
2027
105
105
375
25
2027
60
80
374
0
1831
74
74
374
50
1831
8
16
-------
- 18 -
The adiabatic stirred combustor (ASC) was designed to represent
a segment of the well-known Longwell/Weiss (2-3) jet-stirred reactor. The
output combustion rate achieved in the well-stirred reactor is kinetically
limited when the mixing is maintained at the proper level (2-4). The
intense mixing of the reactants in the well-stirred reactor is due to its
symmetrical geometry and the number and diameter of orifices in the
injector which introduces sonic velocity jets of pre-mixed reactants into
the combustion zone. The recirculation zones established around each of
the sonic jets promotes intense mixing of the reactants with the hot
combustion products.
The adiabatic-stirred-combustion section was followed by a plug
flow zone that was designed to promote as little recirculation as possible
in the area adjacent to the walls of the plug flow zone. Some very slight
recirculation was present, however, because of the finite wall thickness
(0.157 cm.) of the stirred combustor section.
The ASC consisted of three components; an injection tube, the
well-stirred combustion chamber and the plug flow tube. A schematic
diagram of the ASC assembly is given in Figure 2-7. All components were
made of stabilized zirconia*. The injector tube consisted of a 0.635 cm.
outer diameter tube sealed at one end by a hemisphere that contained
seven symmetrically spaced 0.0406 cm. diameter holes drilled with diamond
tip bits. The holes on the 0.254 cm. diameter hole circle were drilled
such that the included angle between opposite holes was 48°. This
injector configuration prevented the gas jets from impinging upon the
reactor walls. The injector tube had a water-cooled stainless steel
"finger" inserted into its 0.447 cm. I.D, such that the tip of the
"finger" was within 0.157 cm. of the hemispherical end of the Zr02 tube.
The annular space between the water cooled "finger" and the I.D. of Zr02
tube was 0.081 cm. This small cross sectional area allowed the air-fuel
mixture to remain cool and thus prevented any pre-reaction before injection
into the stirred combustion chamber. Flash-back was prevented by the high
injection velocity (sonic) of the seven jets. A schematic diagram of the
Zr02 injector is shown in Figure 2-8.
The well-stirred combustion chamber was made of a standard
2.5 cm. outer diameter Zr02 crucible having 0.157 cm. thick walls. The
height of the flat-topped crucible was 2.22 cm. Thirty-seven 0.157 cm.
diameter holes were drilled with diamond bits, on an equilateral triangle
pattern having 0.343 cm. sides. The outermost holes, in some instances,
actually touched the inner wall of the crucible. This design limited the
number of "dead-zones" where recirculation could have taken place. A
schematic diagram of the well-stirred combustion chamber is shown in
Figure 2-9.
2-3 Longwell, J. P. and Weiss, M. A., Ind. Eng. Chem. 4_7, 1634 (1955).
2-4 Hottel, H. C., Williams, G. C., and Miles, G. A., Eleventh Symposium
(International) on Combustion, p. 771, the Combustion Institute, 1967.
* Supplied by ZIRCOA, P. 0. Box 9583, Solon, Ohio 44139. Composition #1192.
-------
- 19 -
FIGURE 2-7
CROSS SECTIONAL VIEW OF ASC ASSEMBLY
INJECTOR
-------
- 20 -
FIGURE 2-8
ZrOg COMBUSTION TUBE INJECTOR
30.48 cm.
—.078 cm.
|-«— .635 cm,—»j
-------
- 21 -
FIGURE 2-9
ZIRCONIA ASC WELL-STIRRED COMBUSTION CHAMBER INJECTOR DESIGN
SCALE: 5/1
DRILL 37 HOLES:
.157 cm. DIAM. ON .343 cm. CENTERS.
-------
- 22 -
In order to prevent impingement of the fuel-air mixture jets upon
the side walls of the combustor, a hollow conical transition piece was molded
from ZrC>2 material such that the included angle of the transition was 70°.
The 0.635 cm. diameter injector tube was located within the base of the
conical transition. The seven injector jets stirred the reaction within
the flat topped conical-walled combustion chamber. The conical volume
within the crucible, including the volume of the 37, 0.157 cm. diameter
holes, was determined to be 4.9 cm-* by measuring the volume of mercury
required to fill the volume with the holes covered up to the point where
the 0.635 cm. hemispherical injector tube was located.
The combustion products were exhausted from the 37 holes of the
combustion chamber, at subsonic velocities in order to avoid the creation
of another well-stirred zone into the 2.5 cm. diameter x 43.18 cm. long
plug-flow zone tube. The laminar* flow of combustion species within the
plug-flow zone was sampled via the quartz-lined, water cooled stainless
steel probe which was manually manipulated with an actuator capable of
moving in both nxial and radial directions.
Table 2-4 summarizes the typical operating characteristics of
each of the three portions which made up the ASC.
2.9.1 Operation of the ASC
The ASC was designed to be installed into the multiburner furnace
with a minimum of down-time such that burners of various geometries could
easily and rapidly be inserted into the electric furnace. Figure 2-7 shows
that the location of the stirred combustor relative to the lower edge of the
tungsten heating element was such that the combustor as well as the plug-flow
tube were uniformally heated to avoid regions of non-adiabatic conditions.
The heavy thermal insulation surrounding the injector tube minimized the heat
transfer between the tungsten heating element and the injector tube. Pre-
reaction of fuel and air at furnace temperature UP to 2300 K was prevented by a
water cooled "finger" that was inserted into the injector tube. A 0.157 cm. gap
between the inch of the water cooled "finger" and the hemispherical tip of
the injector tube minimized heat losses in the ASC that may have been induced
by the presence of the cooled "finger". In this fashion, the reactant mixture
was always injected at uniform temperatures and velocities higher than the
flame propagation velocities for mixtures of air with hydrocarbons, carbon
monoxide or hydrogen.
The electric furnace was never allowed to cool below 1200°K after
being energized since phase transformation within the Zr02 components
occurs below this temperature after the parts have been exposed to tem-
peratures in excess of 1400°K.
* Average flow velocity in the 2.5 cm. diameter tube at 16.98 l/min. flow rate and
2420°K was calculated to be 4.57 meters/sec. The calculated Reynolds number
under these conditions was 214. Therefore, the flow was in the laminar region.
The average flow velocity in one, 0.157 cm. diameter hole of the crucible
under similar conditions stated above was calculated to be 30.5 meters/sec.
The Reynolds number was 34, hence the flow was laminar. In the above cal-
culations the working fluid was assumed to be air which has an absolute
viscosity of approximately 0.08 centipoise at 2420°K. (Maxwell, J. B., Data
Book on Hydrocarbons, D. Van Nostrand Co., Inc., N. Y. 1950.)
-------
- 23 -
TABLE 2-4
TYPICAL OPERATING CONDITIONS FOR THE
ASC STIRRED COMBUSTION ZONE
Reactor Pressure = 102 kPa.
3
ASC Reactor Volume: 4.9 cm . (measured)
Reactant Flow Rates: 17 1/min air, 2.8 1/min Fuel
Reactor Temperature: 1500° - 2200°K
Average Reactor Residence Time: 2 x 10 sec @ 1800°K
Average Reynolds Number @ Exit Plane of one .157 cm. hole: 34
Average Exit Jet Velocity: 28.3 meters/sec calculated from air
flow measurement.
PLUG-FLOW ZONE CONDITIONS
Length of Plug-Flow Zone: 43.18 cm.
Average Velocity @ 1800°K: 3.96 meters/sec
Average Residence Time: 0.106 sec
Reynolds Number: 214
FUEL-AIR INJECTOR
AP across injector 105-140 kPa.
Injection Velocity: 312 meters/sec
-------
- 24 -
Normal operating procedure consisted of setting the furnace
temperature controller at the calculated adiabatic combustion temperature
for a given fuel-air mixture with either ^11,, ^3^8 or as fue^s*
The furnace temperature was then allowed to equilibrate with the water
cooled gas sample probe withdrawn, so as not to cause cooling of the
interior furnace walls. The automatic proportional temperature
controllers compensated for temperature changes when the probe was
inserted into the plug flow tube after the furnace had equilibrated. The
gas sample probe was moved in the X and Y directions until sufficient gas
analysis data were obtained at a given fuel-air mixture, or by varying
one of the test conditions when modified combustion experiments were
conducted. Because of the sensitivity of combustion species concentrations
to small changes in fuel flow rate all of the test data at various axial
and radial probe locations were obtained at fixed fuel settings before
any fuel flow rate changes were made. When the fuel flow rate was
intentionally altered to obtain a different equivalence ratio («5) the
measured combustion species distribution at the new (5 was compared to a
set of base-line data taken at a set of reference coordinates within the
post flame zone to assure comparability on different days.
Combustion species concentration profiles were obtained in the
axial direction between 0.127 and 25.4 cm. from the surface of the well-
stirred combustor and to within 0.033 cm. of the side walls of the plug
flow tube. It was not possible to probe any nearer to these surfaces
without causing damage to the stabilized zirconia components, due to
thermal shock failures caused by allowing the cooled sample probe to
contact the hot surfaces.
When combustion modification conditions such as exhaust gas
recycle and staged combustion were carried out the gas sampling probe was
either removed completely from the plug flow tube or withdrawn to a non-
interrupting position.
2.9.2 Normal Combustion
In order to verify that the ASC was producing a uniform gas
composition at the surface (axial distance = 0.127 cm.) of the burner,
a series of runs were performed with various mixtures of CH4 or CgHg and
air at different firing rates. The results of these tests are summarized
in Tables 2-5, 2-6 and 2-7. These data were obtained with the quartz
sampling probe located at five different radial points across the
2.54 cm. diameter of the burner head and at six different axial distances.
As can be seen from the data, most of the gas sampling was performed in a
zone close to the burner. The data from Tables 2-5 and 2-7 are plotted
in Figures 2-10 and 2-11. Had inefficient mixing occurred inside the
ASC, variations in N0X concentrations would have been observed in the detailed
probing of the gas stream in the zone adjacent to the ASC. The N0X
concentration data indicate that the concentrations were quite uniform
across the diameter of the ASC for a fixed axial position. The run
identification schedule for the methane and propane normal combustion tests
are summarized in Table 2-8. Detailed combustion species data may be found
by locating from Table 2-8 the corresponding run number in the Appendix,
that contains the computer print-out data sheets.
-------
- 25 -
TABLE 2-5
RADIAL PROFILES OF NOx CONCENTRATION ADIABATIC STIRRED COMBUSTOR
C3H0/AIR MIXTURES 0 1873°K
NOy Concentration (PPM)
Axial Distance(cm) 0.127 .635 1.27 1.90 2.54 8.13
Radial Distance(cm)
140 Percent
Stoich. Air
-0.762
7
8
6
6
7
7
-0.381
6
9
6
6
6
10
0.0
6
7
6
6
6
7
0.381
9
9
7
7
7
17
0.762
9
8
6
6
6
16
100 Percent
Stoich. Air
-0.762
13
15
16
15
16
-0.381
13
15
16
17
16
0.0
14
13
14
15
0.381
14
15
14
16
0.762
14
16
16
15
93 Percent
Stoich. Air
-0.762
20
25
25
28
28
-0.381
22
24
26
28
28
0.0
22
21
21
22
22
26
0.381
23
24
23
22
23
0.762
24
23
24
23
23
86 Percent
Stoich. Air
-0.762
29
34
32
34
35
-0.381
31
31
32
35
34
0.0
32
31
30
30
31
42
0.381
28
28
28
29
29
0.762
29
29
27
28
29
80 Percent
Stoich. Air
-0.762
29
38
38
34
29
-0.381
28
30
32
36
31
0.0
35
28
29
31
32
45
0.381
29
28
29
24
31
0.762
30
31
28
30
29
70 Percent
Stoich. Air
-0.762
34
34
35
34
35
43
-0.381
35
36
35
36
36
44
0.0
36
31
33
34
35
46
0.381
36
35
35
36
36
44
0.762
37
35
35
34
35
45
64 Percent Stoich. Air
.762
33
22
26
32
35
.381
31
18
21
28
32
0
35
28
32
31
33
46
.381
31
38
32
32
32
.762
33
29
32
31
33
-------
- 26 -
TABLE 2-6
RADIAL PROFILES OF NOx CONCENTRATION ADIABATIg STIRRED COMBUSTOR (ASC)
CH/, /AIR MIXTURES @ 1873 K
NOy Concentration (PPM)
Axial Distance (cm) 0.635 1.27 1.90 2.54
Radial Distance (cm)
Percent
Stoich.
Air:
112
-0.508
28
32
35
-0. 254
27
33
33
0.0
27
33
33
0.254
26
32
34
0.508
27
33
35
Percent
Stoich.
Air:
64.2
-a 508
1
1
1
-a 254
1
1
1
o.o
0
0
1
2
0.254
1
1
1
0.508
1
1
1
-------
- 27 -
TABLE 2-7
EFFECT OF MIXTURE RATIO ON NOx CONCENTRATION PROFILES
CENTERLINE OF THE ADIABATIC STIRRED COMBUSTOR
CH//AIR MIXTURES @ 1873°K
Firing Rate: 20.04 1/min
NOv Concentration (PPM)
Axial Distance (cm)
0.127
0.635
1.27
1.90
2.54
8.13
% Stoich. Air:
144.3
8
7
6
7
5
8
117.0
14
15
16
18
11
16
97.8
30
32
34
38
29
38
83.5
41
35
36
38
34
43
72.7
33
30
38
41
15
41
64.0
0
0
0
1
6
2
57.0
0
0
NOx CONCENTRATION PROFILES
CENTERLINE OF THE ADIABATIC STIRRED COMBUSTOR
CH/, /AIR MIXTURES (g VARIOUS TEMPERATURES
Firing Rate: 13.78 1/min
Axial Distance: 2.54 cm.
% Stoich. Air
1723 K
NO-y Concentration (PPM)
1813*F
1873 k
2073°K(a)
405
4
4
314
3
5
254
3
8
212
3
16
182
5
33
158
9
68
139
16
115
124
26
18
170
112
30
33
170
102
37
37
93
38
34
80
13
4
69
3
(a) axial distance ¦ 15.11 cm.
-------
40
30
20
10
o
40
30
20
10
o
40
30
20
10
0
- 28 -
FIGURE 2-10
ON PROFILES IN THE ASC WITH CgHg/AIR MIXTURES AT 1873°K
AXIAL DISTANCE: 2.54 cm.
- ~
8—
1
>o
~
~
o
O
A
' ¦
¦
• •
AXIAL DISTANCE:
1.91 cm.
•
0
V
V
A
A
O
o
¦
A
A
¦
AXIAL DISTANCE:
0.127 cm.
¦v
O <1
O <
1
o
O
—• A——A —
~
X
X
l
STOIC H
AIR
70
86
93
100
140
70
86
93
100
140
70
86
93
100
140
.762 -.508 -.254 0 +.254 +.508 +.762
RADIAL DISTANCE (INCHES)
-------
FIGURE 2-11
NO PROFILES IN THE ASC FOR C„H0/AIR AND CH./AIR MIXTURES
X o o 4
1873 K AS A FUNCTION OF AXIAL DISTANCE
AXIAL DISTANCE
8.13 ~-
cm.
V
0.1279*^°"^©
• \
cm.
0.127
cm.
/
ik"
w
150
PERCENT STOICHIOMETRIC AIR
-------
- 30 -
TABLE 2-6
Adiabatic Stirred Combustor
Run Identification for Chemical
Species Concentration Profiles
CH^/Air Mixtures
Firing Rate Wall Temperature
Run #
1/min.
(°K)
340
13.78
2073
341
13.78
1813
343
13.78
1873
344
13.78
1873
347
13.78
1723
362
20.04
1873
363
20.04
1873
379
14.60
1998
380
14.60
2047
381
14.60
2226
382
7.02
2226
383
13.92
2226
For C_H0/Air Mixtures
—
348 15.14 1873
349 15.14 1873
350 15.14 1873
351 16.89 1873
352 16.89 1873
353 16.89 1873
354 16.89 1873
355 16.89 1873
356 16,89 1873
357 16.89 1873
358 16.89 1873
359 16.89 1873
360 16.89 1873
-------
- 31 -
2.9.3 Combustion Parameter Variation in the ASC
Figure 2-12 is the test matrix that was followed to generate the
combustion species concentration profiles in the ASC. Changes in firing
rate (air flow rate), air preheat temperature and molecular fuel composi-
tion were the three variables that were selected for study. The run numbers
inside the box of the matrix identifies the computer print-out data sheet
for that particular set of variables, which appears in the Appendix. The
N0X concentration profiles for each of the runs are also tabulated as
functions of radial and axial dimensions.
2.9.3.1 Reduced Firing Rate and Preheat Effects
The effects of firing rate on N0X formation under adiabatic con-
ditions for CH^/Air mixtures are shown in Tables 2-9 and 2-10. In addition,
the data from Table 2-9 are plotted in Figure 2-13 in terms of residence
times, which were computed from air flow rate and temperature data. The
residence times are extrapolated (indicated by dashed line) for lines
greater than 152 milliseconds which corresponds to an axial location of
25.4 cm. The plug flow zone was 43.18 cm. long and corresponds to a
residence time of about 258 milliseconds at 2073°K for an air flow rate
of 7.02 l/min.
The data plotted in Figure 2-13 show that the temperature as
well as the residence time have strong effects on N0X formation. At both
2073°K (121% stoichiometric air) and 2226°K (100% stoichiometric air)
doubling the residence times produced a two-fold increase in N0X
concentration. However, the slope of the curve at 100% stoichiometric air
and 2226°K was significantly steeper than that at 121% stoichiometric air
and 2073°K, even though the oxygen concentration was lower. For a
residence time of 100 milliseconds, the corresponding N0X concentrations
at 2226°K and 2073°K are 950 ppm and 300 ppm, respectively. It appears,
therefore, that within this range temperature effects can be more important
on N0X formation than residence time and oxygen concentration.
Figure 2-14 shows the effects of air preheat at a near-constant
mixture ratio (132% vs 126% stoichiometric air) of CH^/air with a firing
rate of 14.6 l/min. The two-fold increase in NOx concentration for a
temperature increase of 75°K again indicates the importance of temperature
for N0X formation in the post-flame zone.
Tables 2-11 and 2-12 compare the effect of firing rate on N0X In the
H^/air system at a constant temperature of 2170°K. These data are similar to the
CH^/alr combustion results, in that both fuels exhibit the same residence time
effects at large distances from the face of the stirred zone. Decreasing
the residence time by one-half decreased the N0X by a factor of two. In
both the H2/Air and CH4/Air cases, residence time effects in the vicinity
of the face of the adiabatic reactor seemed to be less important than
those at greater axial distances and hence larger residence times. Therefore,
conventional N0X formation processes appear to prevail.
-------
FIGURE 2-12
ADIABATIC STIRRED COMBUSTOR
TEST MATRIX AND
RUN IDENTIFICATION
Methane
Carbon Monoxide & Hydrogen
Hydrogen
80%
Stoich
Air
100%
Stoich
Air
125%
Stoich
Air
50%
Stoich
Air
140%
Stoich
Air
160%
Stoich
Air
60%
Stoich
Air
120%
Stoich
Air
130%
Stoich
Air
Normal Firing Rate
4J
« a)
Cv| }4
Run
380
Run
381
Run
379
Runs
392
393
Run
391
Run
390
Run
386
Run
387
Run
389
u
ixi cd
O V
cn jcs
CM ol
«3- M
PU
Run
385
Reduced Firing Rate
i*S CD
o a)
oo xl
ON d)
CM M
IX
Run
382
Run
388
4J
NJ to
o a)
CO j3
CM (D
-------
- 33 -
TABLE 2-9
EFFECT OF FIRING RATE ON NO CONCENTRATION PROFILES
CENTERLINE OF THE AD?ABATIC COMBUSTOR
ch4/air mixtures
NO CONCENTRATION (PPM)
Temperature: 2226 K (^7100% Stoich Air)
Axial Distance (cm)
25.4
7.62
2.54 1.27
.635
.127
Firing Rate (1/min)
CR. 14.60
4
860
115
45 37
35
28
7.02
1350
110
51 42
42
41
2073°K CH,
-Air
121% Stoich
Air
Axial Distance (cm)
25.4
7.62
2.54 1.27
.635
.127
Firing Rate (1/min)
7.02
490
58
36 29
27
24
13.92
245
52
29 24
27
18
-------
- 34 -
TABLE 2-10
EFFECT OF MIXTURE RATIO ON NO CONCENTRATION PROFILES
CENTERLINE OF THE ADIABA$IC STIRRED COMBUSTOR
CH4/_AIR_miIIEES
Firing Rate: 14.6 1/mftu
Axial Distance (cm) 25.4 7.62 2.54 1.27 .635 .127
Percent Stoich. Air
NO
Concentration
(PPM)
132 (1998UK)
115
34 K
17
18
17
11
105 (2226°K)
860
115
45
37
35
28
84 (2097°K)
77
63
47
30
39
32
Air Preheated to 170°C
126 (2073UK)
245
52
29
24
21
18
-------
2000
1800
1600
1400
1200
1000
800
600
400
200
0
CENTERLINE NOv CONCENTRATIONS IN CH./AIR AS A FUNCTION OF
TIME AND PERCENT STOICHIOMETRIC AIR IN ADIABATIC STIRRED C
RESIDENCE TIME (MILLISEC.)
-------
320
300
280
260
240
220
200
180
160
140
120
100
80
60
40
20
0
FIGURE 2-14
CENTERLINE NO IN CH./AIR ASC AS A FUNCTION OF AXIAL DISTANCE
X i
FIRING RATE: 14.603 1/MIN.
/[26% STOICHIOMETRIC
/ AIR WITH 170°C PREHEAf]
/ (2073°K)
¦
132% STOICHIOMETRIC AIR
WITH NO PRE-HEAT
(1998°K)
y
J L
20 30
AXIAL DISTANCE (CM)
40
-------
- 37 -
TABLE 2-11
EFFECT OF MIXTURE RATIOS ON NO CONCENTRATION PROFILES
CENTERLINE OF THE ADIABATfc STIRRED COMBUSTOR
H*/AIR MIXTURES
Firing Rate: 13.92 1/min.
Axial Distance (cm)
25.4
7,62 2.54 1.27
.635
.3.27
Percent Stoich. Air
NO Concentration
(PPM)
60 (2183°K)
1
1*1 1
1
1
120 (2170°K)
680
44 18 14
11
10
130 (1958°K)
45
17 10 9
8
7
-------
- 38 -
TABLE 2-12
EFFECT OF FIRING RATE ON NO CONCENTRATION PROFILES
CENTERLINE OF THE ADIABA^IC STIRRED COMBUSTOR
H2/AIR MIXTURES
Percent Stoich. Air:
117-120
(T = 2170°K)
Axial Distance (cm)
25.4
7.62 2.54
1.2.7
0.635 0.
127
Firing Rate (1/min)
13.92
620
34 13
10
8
7
6-96
1150
36 13
9
8
8
EFFECT OF MIXTURE RATIO ON NO CONCENTRATION PROFILES
CENTERLINE 0£ THE ADI-ABATlS STIRRED COMBUSTOR
SflZ-Hg/MR MIXTURES
Firing Rate: 14.60 1/min.
Axial Distance (cm)
25.4
7.62
2.54 1.27 0.635
0.127
(% h2)
Percent Stoich. Air
NO Concentration (PPM)
*45 ll 19
139 (2009"K)
950
160
17
17
125 (2150°K)
930
175
50 33 25
21
15
48 (2150°K)
46
31
19 14 15
14
5
51 (2150°K)
245
160
43 27 17
11
0
-------
- 39 -
2.9.3.2 Variation of NO^ Concentration with Fuel Type
to gain a better understanding of the effects of molecular fuel
structure on NOx formation under adiabatic conditions a series of experiments
were conducted with H2~air and C0-H2~air mixtures. The walls of the ASC
were maintained at theoretical adiabatic flame temperatures for fuel lean
and fuel rich mixtures. The resulting N0X concentration profiles which
were obtained on the centerline of the combustor at various axial distances
from the face of the stirred combustor are summarized in Tables 2-11 and 2-12.
The data showed that under rich conditions and at a firing rate
of 13.9-14.6 1/min., the N0X concentrations 0.127 cm. from the face of the
stirred combustor were 1 ppm for H2, 11 ppm for GO and 14 ppm for CO with
5% H2. Measurements 25 cm. from the surface of the stirred combustor showed
that no change in N0X concentration occurred for the fuel rich H2~air
mixture while the NOx concentrations increased in the case of CO/H2 and
in the case of CO without added hydrogen. This was true even though the
hydrogen/air mixture had an adiabatic flame temperature 33°K higher than
either one of the CO-H2 or CO-air mixtures; the residual oxygen concentration
offers an explanation for these observations. The oxygen burnout is slower
with less hydrogen. Under fuel lean conditions where 15% H2 was added to
CO, the N0X concentration near the face of the burner was 21 ppm while
for the pure H2~air mixture, 10 ppm N0X was measured. At a distance of
25 cm. from the face of the combustor, at similar stoichiometries and
temperatures, the 15% H2-CO mixture produced 930 ppm N0X and the pure
H2~air mixture resulted in 680 ppm N0X.
As will be shown in the next section, the theoretical calculations
indicated that for a stirred reactor operating between 50 and 150%
stoichiometric air, the N0X concentrations increased as H2 addition to
CO was increased from 1 to 10%. The N0X concentration, however, reached
a maximum and decreased as more H2 was added reaching significantly lower
values for fuel rich conditions in the pure H2~air system (see Section 3).
As indicated above, the N0X concentrations measured at a distance of
25 cm. from the face of the stirred combustor were greatest for the rich
CO-air system compared to the H2~air or 5% H2-C0-air mixtures because of
higher residual O2 concentrations.
-------
- 40 -
3. CHEMICAL KINETICS CALCULATIONS
The theoretical calculations conducted during this phase of the
program concentrated on stirred reactor calculations for methane, carbon
monoxide and hydrogen/air combustion. The purpose of these calculations
was primarily to investigate the chemical mechanism for the formation of
N0X and other pollutants in methane-air combustion and also to obtain
comparisons with experimental data for methane, carbon monoxide and
hydrogen air combustion obtained under conditions as free as possible
from fluid mechanical, diffusion and heat transfer limitations. Since
even flat flame experiments conducted at atmospheric pressure were found
to be strongly influenced by diffusional effects in Phase I of this study,
the Adiabatic Stirred Conibustor experiments (described in Section 2 of
this report) were used as the basis for comparison. In the approach to
this series of calculations, consideration was given to all unimolecular
and bimolecular reactions for 25 species of potential importance for
methane/air combustion at one atmosphere, between 1500 and 2500 K. The
species and reaction selection as well as the results of the calculations
are discussed in this section. Further detail on the procedures used will
be found in Reference 3-1.
3.1 Methodology of Kinetics Calculations
While a common approach to studies of kinetic mechanism is to
postulate reaction steps and revise as few steps or rates as possible
to fit the experimental observations, a detailed, objective approach was used
in this study. The technique used involved starting the procedure with
species selection. Previous studies and experience, along with thermochemical
considerations, were used to select species for inclusion in the mechanism.
Next, all possible unimolecular and bimolecular reactions were constructed
by use of a computer code which listed these reactions in the filing order
of the JANNAF Tables. These unimolecular and bimolecular reactions were
then evaluated for potential importance to methane-air combustion under
the conditions of interest (one atmosphere, 1500-2500 K, 80-125% stoichiometric
air). As a result of this evaluation, about two-thirds of the reactions
were found unlikely to be important on the basis of stereochemistry,
thermochemistry or on the basis of relative rates of competing reactions
with the same species.
3-1 Engleman, V. S., "Survey and Evaluation of Kinetic Data on Reactions
in Methane/Air Combustion", Final Report, EPA Contract 68-03-0224,
Report No. EPA-600/2-76-003, (January 1976).
-------
- 41 -
This section describes the methodology used in this process
for methane/air combustion. It should be carefully noted that these
conclusions on the probable relative importance of the reactions considered
pertain only to the chemical and physical constraints of the system
(methane/air combustion, 80-125% stoichiometric air, at one atmosphere
between 1500 and 2500 K). Thus, if one were considering a reaction
system at pressures significantly above or below one atmosphere, or at
temperatures below 1500 K or above 2500 K, or at mixture ratios below
80% or above 125% stoichiometric air, a reevaluation of species, reaction
importance and reaction rates would be required.* In addition, if one
were considering combustion of higher hydrocarbons, combustion of
oxygenated hydrocarbons or conversion of nitrogen-containing species in
combustion, it would be necessary to consider additional species and
reactions, and to re-evaluate the relative importance of reactions considered.
3.1.1 Species Selection
This study was limited to methane/air combustion with subsets
of carbon monoxide/air and hydrogen/air combustion. As such it was
desirable to minimize the number of species considered to keep the
task to a tractable size and yet not eliminate potentially important
species. Species were selected on thermochemical grounds with special
consideration given to species postulated to play a role in methane/air
combustion and pollutant formation. The primary list of 25 species,
along with the considerations that entered into their selection, and
the JANNAF Tables reference for thermochemical data are given in Table 3-1.
* Note that the temperature limitations have definite implications for
the ignition process. Since ignition for plug flow reactors is likely
to occur below 1500°K, additional consideration may be required for
ignition calculations. The pre-screened set may be used as a starting
point for ignition calculations but special attention should be paid
to the results to see if they make sense chemically.
-------
- 42 -
Table 3-1
Primary Species for
Methane-Air Combustion
Log KP
Species
at 2000K
Considerations
JANNAF Reference
CH
-10
hydrocarbon radical
12/67
CHN
-2
possible role in prompt NO
12/69
CKO
+1
stable radical
12/70
ch2
-7
hydrocarbon radical
12/72
ch2o
+1
combustion intermediate
3/61
CH3
+5
hydrocarbon radical
6/69
ch3o
-6
possible role in ignition
constructed from
CH3F 12/63
CH4
-3
starting material
3/61
CN
-6
possible role in prompt NO
6/69
CO
+7
combustion product
3/61
C02
+10
combustion product
9/65
H
-3
combustion intermediate
9/65
NH
-9
possible role in prompt NO
7/72
HNO
-5
possible role in prompt NO
3/63
HO
0
combustion intermediate
12/70
H02
-3
combustion intermediate
3/64
«2
0
combustion product
3/61
k2o
+4
combustion product
3/61
N
-9
important role NO formation
3/61
NO
-2
of prime interest
6/63
no2
-4
oxidation of NO
9/64
"a
0
starting material
3/61
n2°
-6
possible role NO formation
12/64
0
-3
combustion intermediate
6/62
°2
0
starting material
3/61
-------
- 43 -
3.1.2 Reaction List Compilation
By use of a computer code developed for this study, all
mathematically possible unimolecular and bimolecular reactions were
assembled for the 25 species considered. The magnitude of the problem
can be grasped when it is noted that these 25 species result in a list
of 322 reactions. The exponential growth of the number of reactions can
be appreciated from the fact that if the species list is expanded to
around 40 species, over 1000 reactions are mathematically possible. Since
these reaction lists are strictly mathematical constructions, and contain
both elementary reactions and overall reaction steps, further evaluation
of the likelihood of any of these reactions in a physical or a chemical
sense is required.
3.1.3 Reactions of Potential Importance
The relative importance of chemical reactions in a mechanism
depends, to a certain extent, on the goals of the calculation. For the
case of methane/air combustion and pollutant formation, reactions of
importance for N0X formation may be totally unimportant for heat release.
However, many of the combustion reactions are extremely important for N0X
formation. Starting with the list of all mathematically possible
unimolecular and bimolecular reactions, non-elementary reactions were
eliminated. Since activation energy strongly influences reaction rate,
(at 2000 K, 40 kcal/mole is equivalent to four orders of magnitude in the
rate and 100 kcal/mole is equivalent to ten orders of magnitude) thermochemical
considerations were taken into account. Alternate paths and (in a gross
sense) relative concentrations were also considered. Under specific
circumstances a low energy path between intermediates could be unimportant
because of a more favorable alternate path. In other cases a high energy
path may be the only alternative for a reaction of important species, e.g.,
N2 + 0 ¦ NO + N endothermic 75 kcal
Also, for some situations a given reaction will be unimportant because
alternate paths are available with higher concentration intermediates.
In the process of reaction pre-screening on stereochemical
and thermochemical grounds, while there was a major incentive to minimize
the number of reactions retained, marginal reactions were retained to
allow any further eliminations to be done after detailed calculations.
Caution was exercised to avoid elimination of endothermic reactions with
high concentration species unless alternate paths were clearly dominant.
The evaluation of the probable relative importance of all
possible unimolecular and bimolecular reactions of these 25 species
under conditions of interest is given in Appendix B. The original list
of 322 reactions for 25 species was thus reduced to 101 reactions of
potential importance.
-------
- 44 -
3.1.4 Rates for Reactions Used in Kinetics Calculations
The rates used in the present calculations for the reactions
considered to be of potential importance under the conditions of interest
were based on a critical survey of the literature and on estimates for
rates of reactions which were not found in the literature. A detailed
account of survey and evaluation will be found in reference 3-1. The
rates used in the present study (given in Table 3-2) were based on
recommended rates as of December 1974, while the rates given in Reference
3-1 are updated to July 1975. The reactions are written in the filing
order for the kinetics survey. The rates for the forward direction are
indicated as KF and the rates for the reverse direction of the reaction
written are indicated as KR. The values of log A, B, and G are given in
the table where rate = 10loS^T®e~^c/RT^.
3.1.5 Calculations Performed
As indicated earlier, calculations were performed for a
stirred reactor system. Calculations were accomplished with the GKAP code,
developed by Ultrasystems and modified under contract to EPA (68-02-0220) for
the purpose of calculations of combustion/pollutant formation. Primary
attention was focused on stirred reactor calculations of methane/air
combustion using the 101 reactions selected as indicated previously. In
addition, calculations were performed for hydrogen/air and carbon monoxide/
air combustion. Modified combustion runs (preheat, water addition and
flue gas recirculation) were performed for methane/air combustion.
3.2 Results of Kinetics Calculations
The chemical kinetics calculations performed in this study were
aimed at the understanding of the chemistry of combustion and pollutant
formation (with special attention to NO* formation) under conditions where
fluid mechanics, species diffusion and heat transfer were not controlling.
As a result, the perfectly stirred reactor system was used as the model
system to be studied since such a system can also be approached experimentally.
Plug flow calculations such as were accomplished in Phase I of this study
were not pursued since the calculations themselves indicated steep
concentration gradients that would require the inclusion of diffusion
effects and introduce undesirable uncertainty in a study aimed at defining
chemical effects.
A further advantage to the use of a stirred reactor system
for this study is derived from the uniform species and temperature
distribution in a perfectly stirred reactor. This fact greatly simplifies
the theoretical analysis of the chemical system and allows simpler
comparisons with the experimental work. Since the chemical system being
investigated in the stirred reactor is operating at a single steady condition,
the reactions of importance do not vary from point to point within the
reactor or from moment to moment at a given mode of operation.
-------
- 45 -
Table 3-2
LOG A
B
c
RX
1
CH
+CHN
=CH2
+CN ,
KR=
3.00E12,
o
.
o
o
5.0
FX
9
CH
+CH4
= CH2
+CH3 ,
KF =
2.50E11,
0.70 ,
6.0
FX
10
CH
+C02
=CHO
+C0 »
KF =
l.OOElOt
o
•
o
6.0
FX
20
CH
+H0
=CHO
+ H ,
KF =
5.00E11,
0.50 ,
o
•
o
FX
25
CH
+H02
=CH2
+ 02 t
KF =
1.00E10,
0.50 ,
15.0
RX
29
CH
+H2
= CH2
+ H t
KR=
3.OOE11»
O
•
O
26.0
RX
32
CH
+H20
= CH2
+ H0 t
KR=
5.00E11,
o
.
VJ1
O
6.0
FX
38
CH
+N0
=CHN
+0 »
KF =
2.00E12,
o
•
o
o
4
0.0
FX
39
CH
+N0
= CHO
+ N i
KF =
1.50E13,
o
*
o
o
*.
10.0
FX
47
CH
+N2
-CHN
+N »
KF =
2.OOE13»
o
o
.
o
00
•
o
FX
48
CH
+ N2
= CN
+ HN t
KF-
3.00E14,
o
.
o
o
«•
92.0
FX
53
CH
+0
= C0
+H i
KF =
5.00E11,
0.50 ,
0.0
FX
54
CH
+02
=CHO
+0 t
KF =
5.OOE11»
0.50 t
6.0
RX
59
CHN
+CH2
= CH3
+CN ,
KR=
1.OOE11»
o
!*-
•
O
3.0
RX
61
CHN
+CH3
= CH4
+CN ,
KR =
3.OOE 11«
0.70 ,
5.0
RX
64
CHN
+H
= CN
+H2 t
KR=
3.00E12,
o
.
o
o
*
5.0
RX
65
CHN
+HN
= CH2
+N2 ,
KR =
1.00E14,
0.00 ,
70.0
FX
71
CHN
+H0
=CN
+H20 »
KF =
2.OOE11»
0.60 ,
5.0
RX
85
CHN
+0
= CHG
+N .
KR =
1.00E14,
o
.
o
o
0.0
RX
86
CHN
+0
= CN
+H0 »
KR =
3.00E12,
o
o
.
o
3.0
RX
92* CHO
= C0
+H t
KR=
1.50E20,
-1.50 ,
0.0
FX
94
CHO
+CH0
=CH20+C0 ,
KF =
1.50EU,
0.50 »
o
.
o
FX
95
CHO
+CH2
= CH3
+C0 »
KF =
3.00E10,
o
•
o
1.0
RX
98
CHO
+CH3
= CH2
+CH20»
KR»
3.00E10,
o
•
o
6.0
FX
99
CHO
+ CH3
= CH4
+C0 t
KF =
3.OOElit
o
•
o
«•
o
•
o
* Dissociation-reconbination reaction; third-body, H, participates but
is not shown.
-------
- 46 -
Table 3-2 (Continued)
RX103
CHO
+ CH4
LOG A
3
c
=CH20+CH3 ,
KR =
1.00E10,
0.50 ,
6.0
RX104
CHO
+ H
-CH2 +0 ,
KR =
5.00E11,
0.50 ,
4.0
FX 106
CHO
+ H
=C0 +H2 ,
KF =
1.50E12,
0.50 ,
0.0
RX113
CHO
+H0
-CH20+0 ,
KR =
1.00E11,
1.00 ,
3.5
F)CIK
CRD
+H0
=CO +H20 ,
KF =
3.00E10,
1.00 ,
0.0
FX116
CHO
+H02
=CH20+02 ,
KF =
1.00E14,
0.00 ,
3.0
RX119
CHO
+ H2
=CH20+H ,
KR =
1.25E10,
1.00 ,
3.2
RX123
CHO
+ H2Q
=CH20+HG ,
KR =
3.00E10,
1.00 »
0.0
FX127
CHO
+ N
=CO + HN t
KF =
2.00E11,
*i
0
tf\
.
0
2.0
FX 129
CHO
+N0
-CO +HN0 ,
KF =
2.00E11,
0.50 ,
2.0
FXI33
CHO
+ Q
=C0 +HO ,
KF =
3.00E11,
1.00 ,
0.5
FX 134
CHO
+0
=C02 +H ,
KF =
3.00E11,
0.00 ,
0.0
FX135
CHO
+ 02
= CQ +HQ2 ,
KF =
1.50E12,
0.00 »
7.0
FX139
CH2
+ CH4
-CH3 +CH3 i
KF =
1.00E12,
0. »
12.
FXU6
CH2
+ HO
=CH20+H ,
KF =
1.00E13,
0. »
5.
FX147
CH2
+HO
=CH3 +0 ,
KF =
5 .OOElit
0.5 ,
6.
RX150
CH2
+H02
*CH3 +02 ,
KR=
3•OOE12»
0. f
69.5
FX152
CH2
+H2
=CH3 +H »
KF =
3.00E12,
0. f
7.
RX155
CH2
+H2Q
=CH3 +H0 ,
KR=
6.30E10»
0.7 ,
2.
FX159
CH2
~NO
=CH20+N »
KF =
1.50E12,
0. ,
7.
FX165
CH2
+ 02
=CH20+0 ,
KF =
S.OOElli
0.5 ,
7.
RX171
CH20+H
-CH3 +0 »
KR =
5.OOE13•
0. t
0.
RXX 72* CH20+H
=CH30 t
KR =
4.00E40,
-7.5 ,
22.6
RX174
CH20+HN
=CH30+N t
KR=
1.00E14,
0. .
0.
RX177
CH20+H0
=CH3 +02 ,
KR =
3.00E13,
0. ,
20.
* Dissociation-recombination reaction; third-body, M, participates but
is not shown.
-------
- 47 -
Table 3-2 (Continued)
LOG A
B
c
RX178
CH20+H0
=CH30+0 ,
KR =
1.00E14,
0.
"57
RX179
CH20+H02
=CH30+02 ,
KR =
1.00E12,
0.
* 6.
RX181
CH20+H2
=CH30+H ,
KR=
1.00E14,
0.
» 0.
RX184
CH20+H20
=CH30+HQ ,
KR =
3»OOE13*
0.
t o.
RX191*CH3
+H
= CH4
t
KR =
2.00E17,
0.
, 87.5
FX 195
CH3
+HO
=CH30+H ,
KF =
6.30E12,
0.
t 0.
RX 196
CH3
+HO
= CH4
+0 »
KR =
2.00E13,
0.
» 9.
FX19&
CH3
+ H02
=CH4
+02 «
KF=
l.OOEllt
0.5
t 6.
RTI99
CH3
+H2
=CH4
+H ,
KR»
6.3oen»
0.
, 11.9
RX201
CH3
+H20
=CH4
+ H0 t
KR=
3.00E13,
0.
~ 5.
FX206
CH3
+02
=CH30+0 t
KF =
3.00E12,
0.
t 30.
FX216
CN
+N0
= C0
+N2 f
KF =
3.OOE11i
0.
» 0.
FX219
CN
+0
= C0
+N »
KF =
1.00E12,
0.
t 0.
FX220
CN
+ 02
= C0
+N0 »
KF =
3.OOE11i
0.
> o.
FX223
CO
+H0
= C02
+ H t
KF =
1.50E07,
1.3
, -0.76
RX229*
CO
+ 0
= C02
t
KR=
1.00E15,
0.
, 100.
FX230
CO
+02
=C02
+0 »
KF =
3.00E12,
0.
. 50.
RX231*H
+H
= H2
»
KR =
2.OOE14,
0.
, 96.
FX233
H
+ HN0
= HN
~ HO ~
KF*
2.OOE11»
0.5
. 23.
FX234
H
+HNO
»H2
+ N0 t
KF=
1.00E13,
0.
~ 2.5
FX236
H
+ H0
= H2
+ 0 »
KF =
8.00E09,
1.
. 7.
FX237*H
+ H0
= H20
»
KF*
2.00E22,
-2.
, 0.
FX238
H
+ H02
= H0
+H0 ,
KF =
2.50E14,
0.
~ 1.9
FX239
H
+ H02
= H2
+02 ,
KF*
2.50E13,
0.
, 0.7
RX241
H
+ H20
=H0
+ H2 ,
KR*
2.50E13,
0.
, 5.2
* Dissociation-recombination reaction; third-body, M, participates but
is not shown.
-------
- 48 -
Table 3-2 (Continued)
LOG A
B
RX243
H
+N0
= HN
+0 ,
KR =
6.30E11,
0.5
0
RX245
H
+ N0
= H0
+N ,
KR =
6.30E11,
0.5
0
FX248
H
+N02
=H 0
+N0 t
KF =
3.00E14,
0.
1
FX253
H
+N20
=H0
+N2 T
KF=
8.00E13,
0.
15
FX254*H
+0
=H0
i
KF =
8.00E15,
0.
0
.RX255
H
+02
= H0
+0 t
KR=
2.50E13,
0.
0
FX256*H
+02
= H02
»
KF =
2.00E15,
0.
1
FX261
HN
+H0
=H2Q
+N »
KF*
5.OOE11»
0.5
2
RX274
HN
+02
= HN0
+0 ,
KR*
l.OOEU,
0.5
7
FX280
HNO
+H0
=H20
+N0 ,
KF =
3 . OOE13»
0.
0
FX286
HNO
+0
= H0
~NO ,
KF =
5•OOElit
0.5
0
FX291
HO
~HO
= H20
+0 T
KF*
6.30E12,
0.
1
FX292
HO
~HO 2
= H20
+02 ,
KF =
5.00E13,
0.
1
RX295
HO
+N02
= H02
+N0 ,
KR =
1.OOE131
0.
3
FX296
HO
~N20
=H02
+N2 t
KF =
3.00E13,
0.
15
FX297* HO
+0
=H02
*
KF =
1.00E17,
0.
0
RX298
HO
+ 02
= H02
+0 ,
KR=
5.00E13,
0.
1
FX305
N
~NO
«N2
+0 ,
KF =
1.60E13,
0.
0
FX307
N
+N02
=N0
+N0 ,
KF =
4.00E12»
0.
0
FX312
N
+02
= N0
+ 0 »
KF =
6.30E09»
1.
6
RX315
NO
+N0
*N20
+0 »
KR=
1.00E14,
0.
28
RX318* NO
+0
»N02
»
KR=
l.OOElfe.
0.
65
RX319
NO
+02
= N02
+0 f
KR =
1•OOE13r
0.
1
RX320* N2
+0
=N20
f
70
II
5.00E14,
0.
58
RX321
N2
+02
*N20
+0 t
KR»
1.00E14,
0.
28
RX322» 0
+0
*02
~
KR=
2.50E18,
-L.
118
* Dissociation-recombination reaction; third-body, M, participates but
is not shown.
-------
- 49 -
The Phase I study of a nonadiabatic stirred reactor under this
contract showed that experimental results of NOx formation for hydrogen/air
combustion (Figure 3-1) and carbon monoxide/air combustion (Figure 3-2)
could be modeled by a fairly simple chemical mechanism (Reference 3-2)
but that predictions of NOx formation for the combustion of propane/air
in the same combustor seriously underpredicted the results (Figure 3-3).
It should be noted that those calculations were not done with the same
reaction set being described in this report but by an oversimplified
quasi-global mechanism. The results of the present work tend to invalidate
the use of such oversimplified approaches to the treatment of detailed
mechanisms of coupled kinetic phenomena.
For the present theoretical investigation methane/air, hydrogen/air,
and carbon monoxide/air combustion systems were studied for a perfectly
stirred reactor operating adiabatically at one atmosphere. The purpose
of this investigation was to identify the reactions responsible for NOx
formation in hydrocarbon combustion and to study their influence over a
wide range of conditions. In order to investigate the relative importance
of reactions in methane/air combustion under conditions from fuel-rich to
fuel-lean, the pre-screened set of 101 reaction discussed previously was
used as the starting point for the study of methane/air combustion and
appropriate subsets were used for the studies of hydrogen/air and carbon
monoxide/air combustion. The results of the theoretical calculations will
be discussed in this section and the reactions of importance and the
comparison of the theoretical calculations with experimental results will
be discussed in subsequent sections.
3.2.1 Methane-Air Combustion
The combustion of methane-air in an adiabatic stirred reactor
was studied theoretically* for normal combustion between 80 and 125 per cent
stoichiometric air and for modified combustion with preheat, flue gas
recirculation and water addition. Attention was focused on the reactions
that were found to be significant in the mechanism as opposed to the
definition of a minimum set of reactions since the latter definition is
subject to specific experimental criteria and selection of retention criteria.
The initial calculations for methane/air combustion at 100%
stoichiometric air, using the prescreened reaction set, were quite surprising
in light of the previous calculations on propane. Rather than underpredicting
experimental results by a factor of 4 to 10 as had previously been the case
with a quasi-global mechanism (3-2), the predicted N0X levels were orders
of magnitude higher than those found experimentally. The predicted N0X
levels were over 4000 ppm while experimental results were between 10 and
100 ppm. Inspection showed that the reaction responsible for the high N0X
levels was the reaction
CH + N2 HCN + N
3-2 V. S. Engleman, W. Bartok, J. P. Longwell and R. B. Edelman,
Fourteenth Symposium (International) on Combustion, The Combustion
Institute, p. 755 (1973).
* This theoretical system matches the conditions established In the
Adiabatic Stirred Combustor in the experimental part of this study.
-------
- 50 -
FIGURE 3-1
COMPARISON BETWEEN EXPERIMENTAL AND CALCULATED NO
x
CONCENTRATIONS IN A JET-STIRRED COMBUSTOR (FROM REFERENCE 3-2)
HYDROGEN - AIR
P
W
CO
<
W
2
CO
<
•v
s
&
o
£
X!
150
100
50
50
~
~
0
~
100
~ - EXPERIMENT ^
¦ - CALCULATE!'
J L
J L
150
-»-&¦
PER CENT STOICHIOMETRIC AIR
-------
- 51 -
FIGURE 3-2
COMPARISON BETWEEN EXPERIMENTAL AND CALCULATED NO
x
CONCENTRATIONS IN A JET-STIRRED COMBUSTOR (FROM REFERENCE 3-2)
150
100
50
0
50
CARBON MONOXIDE - AIR
O - EXPERIMENTAL
• - CALCULATED
8
J L
100
150
PER CENT STOICHIOMETRIC AIR
-------
- 52 -
FIGURE 3-3
COMPARISON BETWEEN EXPERIMENTAL AND CALCULATED NOv
A
CONCENTRATIONS IN A JET-STIRRED COMBUSTOR (FROM REFERENCE 3-2)
150
PROPANE - AIR
A - EXPERIMENTAL
a - CALCULATED
100
&
k
A
A
50_
A
A
A
0
J I L
J L
&
A L
50
100 150
PER CENT STOICHIOMETRIC AIR
-------
- 53 -
The initially estimated rate coefficient used for this reaction** caused
the reaction rate to be so fast that extremely high levels of both HCN
(760 ppm) and N (2.7 ppm) were predicted which ultimately resulted in
very rapid NO formation. The concentration of N atom was so high, in fact,
that a portion of the Zeldovich mechanism was "running backwards".
N + NO -> N2 + 0
Such a situation might be considered possible under circumstances where
N atoms might be introduced artifically or could be produced in high
concentrations from N-containing species, but must be viewed with skepticism
for methane-air combustion at 100 per cent stoichiometric air.
In an effort to rectify the situation, the assumed rate of the CH + N2
reaction was reduced in sequential steps. The rate constant was reduced
by one order of magnitude, then two, three and finally three and one-half
orders of magnitude to investigate the sensitivity of the calculations.
The reduction in rate constant was accomplished by increasing the activation
energy although arguments could be made for decreasing the preexponential.
It was felt that, since the reaction is spin-hindered, a higher activation
energy might be required to achieve an excited transition state from which
the reaction could be completed.
S
forbidden
HCNN (ground state)
For the case of normal combustion between 80 and 125 per cent stoichiometric
air there would be very little difference whether the activation energy or
the preexponential were adjusted to reduce the rate constant. Within that
range of stoichiometries the temperature variation causes only a factor
of two variation in the rate constant even for the higher activation energy.
A more significant difference would be noted for modified combustion where
the temperature differences would be greater.
** The initially estimated rate coefficient of 2 x 10 e ' was
based on an original estimate by Benson, Golden and Shaw of SRI
(private communication). Their estimate was subsequently revised to
1 x lO^e^^tOOO/RT) as reported in EPA-600/2-75-019.
-------
- 54 -
The initially estimated rate constant used for the CH + N2 reaction,
2 x 10^^ e-^^OOO/RT) ^ resulted in a prediction of 4000 ppm of NOx at
2 msec residence time. With the base rate reduced by one order of magnitude
(by increasing the activation energy by 10 kcal) the N0X level dropped to
2000 ppm. Reducing the base rate by two orders of magnitude, dropped the
NOx level to 300 ppm, and reducing the rate by another order of magnitude
dropped the N0X level to 50 ppm. Another half order of magnitude lower
on the rate constant resulted in a prediction of 39 ppm at 2 msec. Based
on comparison of these calculations with experimental results for the
adiabatic stirred combustor, the rate expression k = 2 x 1013 e_(48,000/RT)
was found to give the be«?t agreement (see Sections 3.3 and 3.4 for further
detail).
Another interesting observation was that the predicted N0X
concentration at 80 per cent stoichiometric air was higher than that at
100 per cent stoichiometric air for all cases except the lowest CH + N2
rate used. This observation is consistent with the fact that peak N0X
formation in the jet-stirred combustor occurs experimentally between
85 and 90 per cent stoichiometric air. The variation in predicted N0X
concentration with activation energy of the CH + N2 reaction is shown
in Figure 3-4. The importance of various reactions and the comparison
with Adiabatic Stirred Combustor data will be discussed in subsequent
sections.
The same set of rate constants was used to predict stirred
reactor performance under modified combustion conditions. Combustion
modification conditions studied were preheat, water addition and flue gas
recirculation. To provide cross-comparisons between calculations, 473 K
preheat was used for all modified combustion.
For the case of 473°K preheat in methane/air combustion in a
stirred reactor the N0X level predicted was 75 ppm at 2 msec residence
time compared to 29 ppm predicted for no preheat. Predicted temperature
was 2155 K compared to 2049 for no preheat. Thus, the increase of
approximately 100 K in combustion temperature resulted in the N0X level
somewhat more than doubling. This indicates an overall activation energy
of 61 kcal over that range of temperature.
For the case of 2% (on air) water addition (equivalent to about
25% on fuel) with 473°K preheat the calculated temperature was 2128 K
compared to 2155 K with no water and 2049 K with no water and no preheat.
Prevaporized water was used in the calculations since 473 K preheat was
used. If liquid water had been used, the heat of vaporization would have
further depressed the temperature. The N0X level calculated for 2% water
addition was 53 ppm, a 30% drop from the 75 ppm without water addition.
At the 5% level of water addition, the temperature dropped to 2088 K with
a corresponding drop in N0X to 36 ppm, better than 50% below the results
for no water addition. Since the results apparently show no effect other
than those expected from the concentration and temperature effects, it is
concluded that water addition under these conditions has primarily a thermal
effect. While there were small effects in the concentrations of the
important intermediates, no major changes in mechanism were noted for
the case of water addition. The concentration of water in the stirred
reactor increased from 17%, in the case of no water addition, to 20%,
in the case of 5% water addition.
-------
- 55 -
FIGURE 3-4
ADIABATIC STIRRED COMBUSTOR METHANE AIR
Q
H
to
<
W
2
CO
<
s
(k
Pi
O
55
X
O - CALCULATED
1000 -
100
NUMBER INSIDE
CIRCLE IS ACTI -
VATION ENERGY
OF CH+N0 (KCAL)
U
RESIDENCE TIME
2 MSEC
10 _
70 80
X
130 140
PER CENT STOICHIOMETRIC AIR
-------
- 56 -
Flue gas recirculation also had a strong thermal effect. At
the level of 10% recirculation (10% of the exhaust gas recirculated—note
that at 50% FGR, the recirculated gas is equal to the fresh reactants to
the burner) the temperature dropped from 2155 K to 1928 K and the N0X
dropped to 9 ppm. At 25% recirculation, the temperature calculated was
1739 K and the N0X was calculated to be 1 ppm. At 50% recirculation the
temperature dropped to 1387 K and the calculated N0X was substantially
less than 1 ppm. At the higher levels of flue gas recirculation, although
only low levels of N0X were formed, the Zeldovich mechanism became dominant
and the CH + N2 reaction played only a minor role. Even though the N2 + 0
reaction has a higher activation energy, the CH concentration dropped off to
make the CH + N2 reaction even slower. No additional mechanism was found
to come into play at lower temperatures in these calculations.
3.2.2 Hydrogen/Air Combustion
Calculations for hydrogen—air combustion were carried out with
the subset of the methane/air reactions that involved only H- 0- or
N-containing species. Adjustments to the rates were not made during the
calculations. The predictions for N0X levels for hydrogen/air combustion
are shown in Figure 3-5.
3.2.3 Carbon Monoxide-Air Combustion
Calculations for carbon monoxide/air combustion were carried
out by adding the CO and CO2 reactions to the hydrogen/air combustion
reaction set. Calculations were performed for both "wet" and "dry" CO
cases. The molar ratios of hydrogen to CO in these cases were 0, 0.01 and
0.10.
It was found that dry CO calculations (H2/CO = 0) resulted in
blowout at all mixture ratios but that ratios of 0.01 and 0.10 resulted
in stable calculations. No search was made for the minimum stable H2/CO ratio.
The calculations for 1% H2 and 10% H2 in CO are illustrated in
Figure 3-6. Peak NOx concentrations appear to occur at about 90 per cent
stoichiometric air in both cases.
3.3 Reactions of Importance for Methane/Air Combustion
The calculations for methane/air combustion and pollutant
formation in a stirred reactor were accomplished using the pre-screened
set of 101 reactions indicated previously. These reactions were used
over the range of 80-125% stoichiometric air and while there were mechanistic
differences among fuel-rich, stoichiometric, and fuel-lean combustion, these
differences were more in matters of degree rather than total changes. The
reactions found to be of importance for the stirred reactor calculations
performed should find application to the combustion zone of conventional
flames. These calculations are not intended to be applicable to the
ignition (or branching) zone and the post-flame zone. The results of
any kinetics calculation are, of course, dependent on the particular set
of rate constants used in the calculations but the comments in this section
are intended to highlight findings of general applicability.
-------
- 57 -
FIGURE 3-5
CALCULATED NC>X LEVELS IN Hg-AIR COMBUSTION
ADIABATIC STIRRED COMBUSTOR H2 ' Am
PER CENT STOICHIOMETRIC AIR
-------
- 58 -
FIGURE 3-6
ADIABATIC STIRRED COMBUSTOR CARBON MONOXIDE-AIR
~ CALCULATED
NUMBERS INDICATE
PERCENT H9 ADDED
TO CO
/
/
® tD<
/ /
//
(D
x
_L
m
\ \
\ \
\ \
* a
w
\\
too
X
~
40
60 80 100 120 140
PER CENT STOICHIOMETRIC AIR
160
-------
- 59 -
The overall mechanism for methane combustion between 80 and 125%
stoichiometric air proceeds primarily through the intermediates CH3, CH2O,
CHO, CO and finally to CO2. That portion of the CH3 that finds its way
to CH3O is returned through CH2O. Small portions of the CH3 proceed
through CH2 and CH but essentially all of these intermediates return
through CH2O, CHO and CO. The reaction path is indicated schematically
in Figure 3-7a,b,c for 80%, 100% and 125% stoichiometric air. The numbers
indicate the percentage of each intermediate proceeding to the next
intermediate, by one or more of the reactions considered. This figure is
intended to illustrate the gross path of the combustion intermediates
between CH4 and CO2. The numbers have been rounded for the purpose of
this illustration. A more complete discussion of the reactions and their
relative importance will be presented later in this section. A schematic
of the combustion reactions and their connection with N0x-forming reactions
is shown in Appendix C. The major feature to be noted in Figure 3-7 is
the similarity between the reaction paths for the main intermediates for
the three stoichiometrics. The main differences occur in the manner in
which CH2 and CH are returned to the main reaction path at the different
stoichiometrics„
While the main combustion path shows relatively minor differences
at the different stoichiometrics, somewhat larger differences are noted
in the reactions of importance for N0X formation. These reactions which
are so important for N0X are relatively unimportant for the gross combustion
mechanism. A species schematic for N0X formation is shown in Figure 3-8.
The figures at the tails of the arrows indicate the percentage of each
intermediate proceeding to the next intermediate, by one or more of the
reactions considered, and the figures at the heads of the arrows indicate
the percentage of each intermediate formed by reaction of the preceding
intermediates. The numbers have been rounded for the purpose of this
illustration.
It is interesting to note that all of the N atoms proceed to
form NO and that N atoms are formed primarily by the breaking of the N2
molecule by oxygen atom or by hydrocarbon radicals. Essentially all of
the NO is formed from N, molecules and N atoms with N20 beginning to
play a role under fuel-lean conditions. For the stirred reactor, any
NO2 that is formed appears to recycle back to NO almost quantitatively.
To examine in more detail specific reactions involved in
methane combustion and pollutant formation in a stirred reactor,
consider the results for the set of 101 prescreened reactions discussed
earlier. Table 3-3 contains information on the production and destruction
of selected species by the reactions found to have the major effects on
those species in the kinetics calculations. The numbers in Table 3-3
refer to the results for the specific rate constants used in these
calculations and are provided for illustration of those results. While
further refinement of the rate constants may result in changing these
numbers, it is expected that the major conclusions that can be drawn
from these calculations would not be negated by such refinements. For
example, the precise percentage of CH4 that reacts by way of CH4 + OH
CH3 + H2O may be changed by refinements in rate constants but the fact
that CH4 + OH CH3 + H2O plays a major role in CH4 breakdown is not
expected to be changed by such refinements.
-------
- 60 -
FIGURE 3-7
PATHS FOR COMBUSTION INTERMEDIATES BETWEEN CH4 AND
A. 80% STOICHIOMETRIC AIR
CH4
100-*.
CHg
70-*.
ch20
100-*-
CHO
lOO*.
CO
100*-
co2
10 2%/C / T /
f 10o\ 50 20 50 50
CHgO
ch2
30
CH
B. 100% STOICHIOMETRIC AIR
ch4
100^.
ch3
65 mi*
ch2o
10CL*.
CHO
100^.
CO
100L*»
co2
» &rT /T /
J; lOOX 65 10 65 35
CHgO
ch2
25^
CH
C. 125% STOICHIOMETRIC AIR
ch4
lOCL^.
CHg
60
ch20
100^
CHO
10(L^
CO
10CL*.
C02
15 2%/ 4 / I /
} 100X 80 10 80 20
CHgO
ch2
10^
CH
-------
- 61 -
FIGURE 3-8a
PATHS FOR INTERMEDIATES INVOLVED IN NOx FORMATION
80% STOICHIOMETRIC AIR
CH,
-------
- 62 -
FIGURE 3-8b
PATHS FOR INTERMEDIATES INVOLVED IN NOx FORMATION
B. 100% STOICHIOMETRIC AIR
N02
-------
- 63 -
FIGURE 3-8c
PATHS FOR INTERMEDIATES INVOLVED IN NOx FORMATION
C. 125% STOICHIOMETRIC AIR
CH,
-------
TABLE 3-3
Production and Destruction of Species by
Specific Reactions for Stirred Reactor Calculations
Species
CH,
Production
Reactions
Per Cent
of Production
at
80 100 125
Destruction
Reactions
Per Cent Stoichiometric Air
Per Cent
of Destruction
at
80 100 125
CH4 + OH CH3 + H20
Per Cent Stoichiometric Air
56 79 86
C04 + H -*¦ CH3 + H2
CH. + 0 -> CH, + OH
4 3
41
3
16
5
7
7
CH.
CH. + OH -+ CH- + H.O
4 3 2
CH4 + H CH3 + H2
CH. + 0 CH_ + OH
4 3
56 79 86 CH3 + 0 -v CH20 + H
41 16 7 CH3 + OH ¦+ CH2 + H20
3 5 7 CH3 + 0 + CH2 + OH
CH3 + H CH2 + H2
CH3 + OH -»¦ CH30 + H
CH_ + H + M CH. + M
3 4
63
12
3
2
9
10
60
17
7
1
11
2
57
17
7
13
1
(T>
ch3o
CH3 + OH -~ CH30 + H
100 100 100
CH30 + M CH20 + H + M
96
97
98
CH20 CH3 + 0 -»¦ CH20 + H 76 67 61
CH30 + M CR20 + H + M 11 12 13
CH2 + °2 CH2° + ° 4 14 20
CH2 + OH -»¦ CH20 + H 7 4 2
CH20 + OH -> CH0 + H20
CH20 + 0 -*¦ CHO + OH
CH20 + H CHO + H2
62
15
23
68
25
7
67
30
3
-------
TABLE 3-3 (Continued)
Species
CH„
Production
Reactions
CH3 + OH CH2 + H20
CH3 + 0 -»¦ CH2 + OH
CH3 + H -> CH2 + H2
Per Cent
of Production
at
80 100 125
"Per Cent Stoichiometric Air
70
Destruction
Reactions
68
17
14
70
22
4
28
2
ch2 + o2 ch2o + 0
CH2 + OH
CH20 + H
CH2 + 0 + CHO + H
CH2 + OH
CH + H20
Per Cent
of Destruction
at
80 100 125
Per Cent Stoichiometric Air
20 49 75
31
16
32
16
12
23
7
7
11
CH
CH2 + OH -> CH + H20
97
99 100
CH + 02 -»¦ CHO + O
CH + OH CHO + H
CH + 0 -f CO + H
24
18
40
55
9
29
78
3
18
0>
Ln
CHO
CH20 + OH CHO + H20
CH20 + 0 CHO + OH
CH20 + H -*¦ CHO + H2
CH2 + 0 -> CHO + H
CH + 02 -*• CHO + 0
CH + OH + CHO + H
57
14
21
3
2
1
63
23
6
3
3
1
64
29
3
2
2
CHO + M-> CO + H + M
92
93
94
CO
CHO + M-> CO + H + M
89 91 93 CO + OH + C02 + H
CO + 0 + M C02 + M
89
11
93 95
7 5
-------
TABLE 3-3 (Continued)
Species
C0„
Production
Reactions
Per Cent
of Production
at
80 100 125
CO + OH •*- C02 + H
CO + 0 + M C02 + M
Per Cent Stoichiometric Air
89 93 95
11 7 5
Destruction
Reactions
Per Cent
of Destruction
at
80 100 125
Per Cent Stoichiometric Air
HCN
CH + N2 -*¦ HCN + N
CH + NO HCN + 0
CH, + CN -> HCN + CH,,
4 3
CH2 + N2 + HCN + NH
52
36
8
3
58
31
4
6
64
21
4
10
HCN + 0 CHO + N
HCN + OH -> CN + H20
81 81
18 19
57
43
CN
HCN + OH + CN + H20
97 99 99 CN + CH. -»• CH0 + HCN
4 3
CN + 02 -»¦ CO + NO
CN + 0 -~ CO + N
63
12
15
24
52
21
12
76
10
N
CH + N2 HCN + N
HCN + 0 + CHO + N
N2 + 0 NO + N
CH + NO CHO + N
CH2 + NO -*• CH20 + N
33
36
5
14
9
19
23
42
7
7
11
8
73
2
5
N + OH -»¦ NO + H
N + 02 + NO + 0
96
4
83
17
59
41
-------
TABLE 3-3 (Continued)
Species
NO
Production
Reactions
N + OH -*¦ NO + H
Per Cent
of Production
at
80 100 125
Destruction
Reactions
Per Cent Stoichiometric Air
83 40 16 NO + CH HCN + 0
Per Cent
of Destruction
at
80 100 125
Per Cent Stoichiometric Air
42 14
N + 02 -*¦ NO + 0
N2 + 0 -»¦ NO + N
N02 + H NO + OH
N20 + 0 NO + NO
4 9 11 NO + CH CHO + N
5 21 20 NO + H02 N02 + OH
5 23 37 NO + 0 + M ^ N02 + M
2 11 NO + CH2 -*¦ CH20 + N
25
7
4
18
9
51
13
9
85
15
NO„
NO + HOz N02 + OH
NO + 0 + M N02 + M
61 79
39 21
85
15
N02 + H -> NO + OH
100 98
95
ON
-------
- 68 -
The numbers shown in Table 3-3 represent the relative
contribution of a given reaction to the sum of all of the reactions that
produce or destroy a given species. The numbers do not represent the
absolute level of production or destruction. In fact the major "production"
of CH4, N2, and O2 occurs from the input of these species as reactatits.
If there were entries for production of CH4 in the table, the major
reaction for production of CH4 would be insignificant compared to the
reactant input. As another example it will be noted that at 125%
stoichiometric air the only destruction reactions for NO result in the
formation of NO2. It should be noted, however, that very little of the
NO is destroyed in. this manner relative to the NO output from the reactor
and most of the NO2 so formed is destroyed by a reaction that produces NO.
Since the main path for the combustion reactions involves
CH4 CH3 -*• CH2O CHO -+ CO ->• CO2, the production and destruction
reactions for these species are readily ascertained by inspection of
Table 3-3. The production and destruction of some of the minor species
is not so straightforward and will be discussed in more detail here.
The species of prime interest for this study is NO and
therefore attention will be focused on NO and its precursors. Working
backwards from NO, the following observations are noted:
• NO production is dominated under fuel rich and stoichiometric
air conditions by reactions of N atoms with N + OH more
important than N + O2.
• NO production from N2 + 0 is relatively unimportant under
fuel rich and relatively important under fuel lean conditions
• Production of NO from NO2 results from the loop
NO -*¦ N02 -* NO.
• Production of NO from N2O begins to become significant
under fuel lean conditions but is not dominant at 125%
stoichiometric air.
Going back one step to N atom, the following observations are noted:
• Under fuel rich conditions N is produced primarily by
CR + N2 •* HCN + N.
• Moat of the HCN produced by CH + N2 -*¦ HCN + N also ends
up as N.
• Under stoichiometric air conditions the N from GH + N2
and from HCN is comparable to that from N2 + 0.
• Under fuel lean conditions N is formed primarily from
N2 + 0 + NO + N.
-------
- 69 -
Examining the reactions of importance for CH it is found that:
• While CH + N2 -* HCN + N is important for N atom production
and HCN production, it does not play a major role in CH
destruction (less than 1%).
• CH is produced primarily by CH2 + OH -»¦ CH + H2O.
• CH is destroyed by reactions with 0, OH and O2.
Since CH is produced almost exclusively from CH2, inspection
of the CH2 reactions indicates:
• Between 10 and 30% of the CH2 winds up as CH through the
reaction CH2 + OH -»¦ CH + H20.
• CH2 is produced almost exclusively from CH3 by reactions
with OH, 0 and H.
• Between 15 and 25% of the CH winds up as CH2•
• CH3 is produced from CH4 and CH^ goes primarily to CH3.
Regarding HCN
• HCN is produced primarily by CH + N2 -*¦ HCN + N and
secondarily from CH + NO -+¦ CHN + 0.
• HCN ultimately yields N or CN in the present calculations.
• The CN, resulting primarily from HCN, yields NO or HCN or
N atom which ultimately result in NO.
Thus, from the above observations the key reactions that should
receive further study are first, the most obvious
CH + N2 HCN + N
and second, the reactions that produce CH such as
CH2 + OH -* CH + H20
and that produce CH^ such as
CH3 + OH CH2 + H20
It might in fact be easier to study the reverse of the last two reactions
even though the forward rate is of primary interest. Measurements of
N atom concentrations as well as CH and CH2 concentrations in a stirred
reactor would provide valuable insight into the kinetics and iqechanism
of NO formation in flames.
Thus, hydrocarbon species appear to play a major role in NO*
formation in the flame zone under specific conditions. This would imply
that under conditions where NO* in the flame zone could be important
(i.e. when one is trying to reduce NOx emissions below 100 ppm) the CH
concentration could play a major role»
-------
- 70 -
3.4 Comparison of Theoretical Calculations
with Experimental Results
The kinetics calculations for hydrogen/air, carbon monoxide/air
and methane/air combustion under normal firing conditions were compared
with experimental results reported in Section 2. Those comparisons are
reported in this section.
The experimental results for hydrogen/air combustion were
limited to temperatures below 2200 K and therefore only limited data
were taken in the adiabatic stirred combustor. However, where data were
available the agreement with calculations was good as shown in Figure 3-9.
The experimental results for carbon monoxide/air were restricted
to the same upper temperature limit as the hydrogen data. Experiments
were conducted with hydrogen addition ranging from 0-17% of the carbon
monoxide. Calculations were performed for 0, 1, and 10% hydrogen addition.
While the 1% and 10% additions yielded stable solutions, the 0% calculation
indicated blowout. No attempt was made to dry the air in the experimental
system and the moisture content of the air used is uncertain although
reasonably dry. The experimental results are compared with the calculations
in Figure 3-10 and show reasonably good agreement.
The methane/air experiments were run over the range 85-130%
stoichiometric air at a residence time of 2.5 milliseconds. Host of
the calculations were performed at 2 milliseconds with variations to
3 and 5 milliseconds. The plot and the shape of the curve shown in
Figure 3-11 are based on the parametric variation of the CH + N2 reaction
rate and comparison with previously obtained stirred reactor data as
discussed in Section 3.2. The final rate used for the CH + N2 reaction*
was kf = 2 x io!3e-(48,000/RT). This matching procedure is also in good
agreement with extensive stirred reactor data on methane/air taken previously
on a non-adiabatic system.
* The final rate was 3.5 orders of magnitude lower than the base case
estimate.. All of the adjustment was made in the activation energy as
discussed previously. However, while the experimental data definitely
indicated that the rate had to be slower than the original estimate,
it could not be determined unequivocally whether the preexponential
should be lower or the activation energy should be higher.
-------
- 71 -
FIGURE 3-9
ADIABATIC STIRRED COMBUSTOR HYDROGEN-AIR
140
120
Q
H
w 100
<
w
2
CQ
80
3
&
&
o* 60
40
20
40 60 80 100 120 140 160
PER CENT STOICHIOMETRIC AIR
OcALCULATEE
lEXPERIMENT
o
O O
« »
-------
- 72 -
FIGURE 3-10
ADIABATIC STIRRED COMBUSTOR CARBON MONOXIDE-AIR
140 _
120 _
100
80
60
40 _
20
11
x
~ CALCULATED
¦ EXPERIMENTAL
NUMBERS INDICATE
PERCENT H9 ADDED
TO CO
/ /
//
//
//
/
~
0 0.
//
\ \
ID
v S3
\\
\\
m
117
±
ID
60 80 100 120 140
PER CENT STOICHIOMETRIC AIR
160
-------
- 73 -
FIGURE 3-11
ADIABATIC STIRRED COMBUSTOR METHANE AIR
140 _
120 _
Pi.
O
X 60
40 _
(^CALCULATED
(experimental
RESroENCE TIME
q 2.5 MSEC
W
m 100
<
W
S
< 80
4 S
20 _ \
u \
40 60 80 100 120 140 160
PER CENT STOICHIOMETRIC AIR
-------
- 74 -
4. CONCLUSIONS AND RECOMMENDATIONS
The Adiabatic Stirred Combustor has been shown to be a useful tool
for the study of the chemistry of combustion coupled to pollutant
formation
- The stirred zone was shown to be well-stirred, matching the
results of the jet-stirred combustor with hemispherical
geometry under comparable conditions.
- The radial profiles at the exit of the stirred zone were
shown to be flat and continued to be flat downstream of the
stirred zone.
The approach to kinetics calculations of combustion by starting
from a reaction set containing all possible unimolecular and bimolecular
reactions was shown to be valuable for the investigation of methane/air
combustion. This approach allows investigation of competitive mechanisms
that might otherwise be overlooked by an intuitive approach to such a
complex system. It should be noted, however, that the success of such
an approach is also dependent on the accuracy with which the individual
rate constants are known. In addition, the magnitude of the task
increases exponentially with the number of species considered. This
fact makes the analysis of the combustion of higher hydrocarbons more
difficult using this technique.
The calculations for hydrogen and carbon monoxide combustion in the
adiabatic stirred combustor match the data quite well.
The formation of NO during combustion of methane/air in the adiabatic
stirred combustor is also matched well and the results lead to some
interesting conclusions:
(a) The formation of N0X is controlled by the concentrations
of both N atoms and 0 atoms.
(b) Under fuel lean conditions the concentration of N atoms is
controlled by the concentration of 0 atoms through the reaction
N2 + 0 NO + N.
(c) Under fuel rich conditions, however, the concentration of
N atoms is controlled by the reaction CH + N2 -*¦ HCN + N
and the production of NO is predominantly through N atoms
by way of N + OH -> NO + H. The HCN produced eventually
results in the formation of more N atoms.
(d) Under stoichiometric air conditions, the production of N
atoms is balanced between N2 + 0 N + 0^ and CH + Ng ¦+ HCN + N.
The results of these calculations indicate that further study is
warranted on the reaction CH + N2 -*¦ HCN 4- N. Studies are also warranted
on the reactions that lead to CH formation such as CH2 + OH CH + H2O
and CH3 + OH -*¦ CH2 + H2O. Reactions of HCN that lead to the formation
of N atom should also be studied.
-------
- 75 -
6. Measurements of the concentrations of species such as N, CH, and CH2
during hydrocarbon combustion are required for the further elucidation
of the mechanism of N0X formation.
7. Calculations on combustion modification experiments in the stirred reactor
indicate that further information on the key reactions in N0X formation
could be obtained from such experiments. The activation energy of the
CH + N2 reactions could be investigated by flue gas recirculation
experiments with either real or simulated flue gases.
8. New calculation techniques should be developed to determine the sensitivity
of a given mechanism to each of the component steps. Such techniques
would be valuable for application to complex combustion mechanisms such
as studied in this investigation. This would allow a determination of
the most crucial reactions and the sensitivity of the result to these
reactions without individual or multiple repetitive rate adjustments.
9. As new information on the individual reaction rates becomes available,
this information should be factored into the set of recommended rates.
This is especially important for the key reactions in the mechanism.
10. Understanding of the coupling of the combustion mechanism with NOx
formation becomes increasingly important as the target NOx levels
become lower. An understanding of the involvement of hydrocarbon
radicals in the NO formation mechanism through reactions such as
CH + N2 - CHN + N is important both under conventional combustion as well
as under modified combustion conditions. Under conditions where this
reaction plays a major role, the N atom concentration becomes more
important than the 0 atom concentration in determining N0X levels.
In fact only very low concentrations of CH can result in major changes
in NO.
-------
APPENDIX A
DATA LISTINGS
RUN NUMBER 333
PREMIXEO FLAT FLAME BURNER
STAGEO COMBUSTION
METHANE COLD WALL
PRIMARY PRIMARY SEC. OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RADIAL
WALL
NO
NOX
02
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOIC
DIST
DIST
TEMP
CCFM)
(CFM)
AIR
(CFM)
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.076
0.866
119.6
0.000
119.6
32.50
C.00
16
17
3.50
0.000
8.14
0.
0.082
0.866
110.3
O.OCO
110.3
32.50
0.00
29
31
2.70
0.000
8.87
0.
0.088
0.866
102.2
0.000
102.2
32.50
O.CO
58
60
1.60
0.000
9.60
0.
0.095
0.866
95.1
0.000
95.1
32.50
0.00
68
90
C. 14
0.000
10.98
0.
0.102
0.866
88.8
0.000
88.8
32.50
0.00
68
69
C.09
1.240
9.92
0.
0.076
0.866
119.6
0.219
149.9
32.50
0.00
11
12
6.20
C.000
6.59
c.
0.0B2
0.866
110.3
0.219
138.3
32.50
0.00
26
27
5.10
0.000
7.21
0.
0.088
0.866
102.2
0.219
128.1
32.50
0.00
47
48
4.30
0.000
7.83
0.
0.095
0.866
95.1
0.219
119.2
32.50
0.00
68
69
3.30
0.000
8.66
0.
0.102
0.866
88.8
0.219
111.3
32.50
0.00
38
45
3.10
1.182
7.93
0.
0.076
0.866
119.6
0.291
159.9
32.50
0.00
11
12
6.60
0.000
6.18
0.
0.082
0.866
110.3
0.291
147.5
32.50
0.00
23
24
5.90
0.000
6.69
0.
0.088
0.866
102.2
0.291
136.7
32.50
0.00
50
51
5.00
0.000
7.42
0.
0.095
0.866
95.1
0.291
127.2
32.50
0.00
70
70
4.00
0.000
8.14
0.
0.102
0.866
88.8
0.291
118.8
32.50
0.00
38
47
3.90
1.269
7.31
0.
-------
RUN NUMBER 334
PREMIXEO FLAT FLAKE BURNER
STAGED COMBUSTION
METHANE
COLD WALL
PRIMARY
PRIMARY
SEC.
OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RADIAL
WALL
NC
NOX
02
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOIC
DIST
DIST
TEMP
(CFM)
(CFM)
AIR
(CFM)
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.076
0.866
119.6
0.364
170.0
32.50
0.00
8
9
7.40
0.000
5.66
0.
0.082
0.866
110.3
0.364
156.8
32.50
O.CO
20
21
6.60
0.000
6.28
0.
0.088
0.866
102.2
0.364
145.3
32.50
O.CO
39
40
5.70
0.000
6.90
0.
0.095
0.866
95.1
0.364
135.2
32.50
0.00
58
58
4.80
0.000
7.52
0.
0.102
0.866
88.8
0.364
126.2
32.50
0.00
30
39
4.60
1.125
7.00
0.
0.076
0.866
119.6
0.438
180.2
32.50
0.00
9
10
7.80
0.000
5.46
0.
0.082
0.866
110.3
0.438
166.2
32.50
0.00
20
21
7.00
0.000
5.87
0.
0.088
0.866
102.2
0.438
154.0
32.50
0.00
37
38
6.30
0.000
6.48
0.
0.095
0.866
95.1
0.438
143.3
32.50
0.00
52
54
5.40
C.000
7.21
0.
0.102
0.866
88.8
0.438
133.8
32.50
0.00
16
33
5,30
0.872
6.69
0.
-------
RUN NUMBER 335
PREMIXED FLAT FLAME BURNER
STAGED COMBUSTION
METHANE COLD HALL
PRIMARY PRIMARY SEC. OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RADIAL
MALL
NO
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOIC
DIST
OIST
TEMP
(CFM)
(CFM)
AIR
CCFM)
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.076
0.866
119.6
0.000
119.6
32.50
0.00
22
22
3.50
0.000
8.25
0.
0.0B2
0.866
110.3
0.000
110.3
32.50
0.00
45
45
2.30
0.000
9.08
0.
0.088
0.866
102.2
0.000
102.2
32.50
0.00
78
79
0.94
0.000
10.49
0.
0.095
0.866
95.1
0.000
95.1
32.50
0.00
73
75
C .09
0.493
10.73
0.
0.102
0.866
88.8
0.000
88.8
32.50
0.00
50
5
C.08
2.506
9.19
0.
0.076
0.866
119.6
0.219
149.9
32.50
0.00
17
17
6.00
0.000
6.90
0.
0.082
0.866
110.3
0.219
138.3
32.50
0.00
33
34
4.90
0.000
7.52
0.
0.088
0.866
102.2
0.219
128.1
32.50
0.00
64
64
3.90
0.000
8.25
0.
0.095
0.866
95.1
0.219
119.2
32.50
o.co
50
51
3.30
0.734
8.14
0.
0.102
0.866
88.8
0.219
111.3
32.50
0.00
27
34
3.20
2.070
7.62
0.
0.076
0.866
119.6
0.291
159.9
32.50
0.00
17
18
6.50
C.000
6.38
0.
0.082
0.866
110.3
0.291
147.5
32.50
0.00
31
32
5.70
C.000
7.10
0.
0.088
0.866
102.2
0.291
136.7
32.50
o.co
52
53
4.80
0.000
7.73
0.
0.095
0.866
95.1
0.291
127.2
32.50
0.00
36
48
4.10
0.519
7.73
0.
0.102
0.866
88.8
0.291
118.8
32.50
0.00
8
32
4.00
1.845
7.00
0.
-------
RUN NUMBER 336
PREMIXED FLAT FLAME BURNER
STAGED COMBUSTION
METHANE
COLO WALL
PRIMARY
PRIMARY
SEC.
OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RADIAL
WALL
NC
NOX
C2
CG
C02
HC
FLOW
FLOW
STCIC
FLOW
STOIC
DIST
DIST
TEMP
(CFM)
(CFM)
AIR
(CFM)
AIR
( IN)
( IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.076
0.866
119.6
0.364
170.0
32.50
0.00
13
14
7.30
0.000
5.87
0.
0.082
0.866
110.3
0.364
156.8
32.50
0.00
28
28
6.40
0.000
6.48
0.
0.088
0.866
102.2
0.364
145.3
32.50
0.00
55
56
5.60
0.000
7.21
0.
0.095
0.866
95.1
0.364
135.2
32.50
0.00
25
42
5.00
0.573
7.21
0.
0.102
0.866
88.8
0.364
126.2
32.50
0.00
7
29
4.80
1.689
6.48
0.
0.076
0.866
119.6
0.438
180.2
32.50
0.00
15
15
7.80
0.000
5.56
0.
0.082
0.866
110.3
0.438
166.2
32.50
0.00
30
30
6.90
0.000
6.28
0.
0.088
0.866
102.2
0.438
154.0
32.50
0.00
53
54
6.10
0.000
6.90
0.
0.095
0.866
95.1
0.438
143.3
32.50
0.00
26
38
5.60
0.546
6.79
0.
0.102
0.866
88.8
0.438
133.8
32.50
0.00
5
25
5.50
1.877
6.07
0.
-------
RUN NUMBER 340
ADIABATIC STIRRED COMBUSTCR
NORMAL CGMBUSTION
METHANE HOT WALL
FUEL AIR PCT AXIAL RAOIAL WALL NO NOX
FLOW FLUW STOIC OIST DIST TEMP
(CFM) (CFM) AIR (IN) (IN) (C) (PPM) (PPM)
0.018
0.606
345.4
5.95
0.00
1800
3
4
0.023
0.606
269.3
5.95
0.00
1800
4
5
0.028
0.606
219.8
5.95
O.OC
1800
6
8
0.034
0.606
184.9
5.95
C.CC
18C0
13
16
0.040
0.606
159.1
5.95
O.OC
18C0
27
33
0.045
0.6C6
139.3
5.95
O.OC
1800
56
68
0.051
0.606
123.5
5.95
O.OC
1800
97
115
0.057
C.606
110.8
5.95
O.OC
1800
150
170
0.063
0.606
100.2
5.95
C.OC
1800
160
17C
0.051
0.606
123.5
5.95
0.00
1800
140
155
G2
CO
C02
(PCT)
(PCT)
(PCT)
16.00
o.ooc
3.25
14.80
o.ooc
3.94
12.90
o.ooc
4.95
1C .90
o.ooc
5.97
8.90
o.ooc
6.90
6.60
o.ooc
7.93
4.70
0.028
8.87
2.60
0.079
9.71
0.90
0.899
10.73
5.10
0.028
8.66
-------
RUN NUMBER 341
ADIABAT1C STIRRED COMBUSTCR
NORMAL CCM8USTION
METHANE
HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
CIST
( IN)
RADIAL
DIST
( IN)
WALL
TEMP
(C )
NO
(PPM)
NOX
(PPM)
0.018
0.606
345.4
1.00
O.CC
1540
2
4
0.018
0.606
345.4
l.CO
-C.1C
1540
1
3
0.018
0.606
345.4
1.00
0.1C
1540
1
3
0.018
0.606
345.4
1.00
0.20
1540
1
3
0.018
0.606
345.4
1.00
-C.20
1540
3
0.023
0.606
269.3
1.00
-0.2C
1540
1
3
0.023
0.606
269.3
l.CO
o.oc
1540
1
3
0.028
0.606
219.8
l.CO
c.cc
1540
1
3
0.023
C.606
269.3
l.CO
-c.ic
154C
1
3
0.023
0.606
269.3
l.CO
c.ic
1540
1
3
0.023
0.606
269.3
l.CO
C.2C
1540
1
3
0.023
C.606
269.3
l.CO
o.oc
154C
1
3
0.023
0.606
269.3
l.CO
-C.2C
1540
1
3
0.028
0.606
219.8
l.CO
-C.IC
1540
1
3
0.028
0.606
219.8
l.CO
-C.2C
1540
1
3
0.028
0.606
219.8
1.00
0.1C
1540
1
3
0.028
0.606
219.8
1.00
0.20
1540
1
3
0.028
0.606
219.8
1.00
0.00
1540
1
3
0.034
0.606
164.9
l.CO
O.OC
1540
1
3
0.034
0.606
164.9
l.CO
0.1C
1540
1
3
0.034
0.6C6
184.9
l.CO
C.2C
1540
1
3
0.034
0.606
184.9
l.CO
-0.1C
154C
1
4
0.034
C.606
184.9
l.CO
-C.2C
154C
1
4
02
CO
C02
HC
(PCT)
(PCT)
(PCT)
(PPM)
14.00
0.028
0.84
3
14.00
0.028
0.84
3
13.50
C.OCC
0.84
4
13.00
C.OOC
0.84
4
13.50
O.OOC
0.84
4
13.50
0.079
1. 12
5
13.20
0.104
1.22
5
12.CO
0.232
2.27
5
12.40
C.232
1.69
4
12.00
C .206
1.69
4
12.60
0.2C6
1.60
6
12.9C
C.2C6
1.6C
5
12.50
0.181
1.50
4
11.40
0.258
2.37
4
11.10
0.283
2.46
5
10.80
0.283
2.56
6
10.90
C. 309
2.66
6
11.40
C.258
2.56
5
9.60
0.44C
3.94
5
9.10
0.414
4.24
5
8.8C
C.388
4.44
5
9.4C
C.44C
4.04
5
9.4C
C.44C
4.04
5
-------
RUN NUMBER 341 CDNT
ADIABATIC STIRRED COMBUSTOR
NORMAL CGMBUSTION
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.040
0.606
159.1
1.00
-C.2C
1540
2
5
0.040
0.606
159.1
1.00
-C.1C
1540
2
5
0.040
0.606
159.1
1.00
o.oc
1540
2
5
0.040
0.606
159.1
l.CO
0.1C
1540
3
5
0.040
0.606
159.1
I.00
C.2C
1540
3
5
0.045
0.606
139.3
l.CO
0.2C
1540
6
8
0.045
0.606
139.3
1.00
0.1C
1540
6
8
0.045
0.606
139.3
1.00
0.00
1540
7
9
0.045
0.606
139.3
1.00
-0.10
1540
7
9
0.045
0.606
139.3
1.00
-0.20
1540
7
9
0.051
0.606
123.5
1.00
-0.20
1540
12
15
0.051
0.606
123.5
1.00
-0.10
1540
12
15
0.051
0.606
123.5
1.00
C.OC
1540
12
16
0.051
0.606
123.5
1.00
0.1C
1540
12
15
0.051
0.606
123.5
1.00
C.2C
1540
11
14
0.057
0.606
110.8
l.CO
0.2C
1540
18
23
0.057
0.606
110.8
1.00
0.1C
1540
19
25
0.057
0.606
110.8
1. GO
O.OC
1540
19
26
0.057
0.606
110.8
1.00
-0.1C
1540
19
26
0.057
0.606
110.8
1.00
-C.2C
1540
19
27
C 2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
6.80
0.181
5.97
6.90
0.181
5.97
6.90
0.155
5.97
6.80
C. 129
5.97
6.70
0.079
5.87
5.30
0.028
6.90
5.40
0.000
7.00
5.60
0.028
7.00
5.60
0.028
6.90
5.50
0.028
6.90
4.10
0.028
7.73
4.10
0.053
7.83
4. 20
0.053
7.73
4.20
C.028
7.73
4.20
0.028
7.62
2.70
0.079
8.56
2.60
0.079
8.66
2.70
0.129
8.56
2.60
0.129
8.46
2.60
0.104
8.56
6
4
4
4
4
5
5
5
4
5
3
4
4
5
5
5
5
6
5
4
-------
RUN NUMBER 343
ADIABATIC STIRRED COMBUSTCR
NORMAL CCMBUSTIQN
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFMI (CFM)
PCT AXIAL
STOIC CIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.063
0.606
100.2
l.CO
C.OC
1600
27
33
0.063
0.606
100.2
1.00
-0.1C
1600
27
33
0.063
0.606
100.2
1.00
0.1C
1600
27
34
0.063
0.606
100.2
1.00
0.20
1600
28
35
0.063
0.606
100.2
1.00
-0.20
1600
28
35
0.063
0.606
100.2
0.75
O.OC
16C0
27
33
0.063
0.606
ICO.2
0.75
-0.1C
1600
27
32
0.063
0.606
100.2
0.75
C.1C
1600
28
33
0.063
0.606
ICO.2
0.75
0.2C
1600
28
33
0.063
0.606
ICO.2
0.75
-0.20
16C0
27
32
0.063
0.606
100.2
0.75
O.OC
1600
24
29
0.063
0.606
ICO.2
0.75
-0.1C
1600
25
30
0.063
0.606
100.2
0.75
0.10
1600
25
29
0.063
0.606
100.2
0.75
0.20
1600
25
30
0.063
0.606
100.2
0.75
-0.20
1600
25
3C
0.063
0.606
100.2
0.25
O.OC
1600
22
27
0.063
0.606
ICO.2
0.25
-0.1C
160C
22
27
0.063
0.606
100.2
0.25
0.1C
16C0
22
26
0.063
0.606
ICO.2
0.25
0.20
1600
22
27
0.063
0.606
ICO.2
0.25
-0.2C
1600
23
28
0.063
0.606
100.2
0.25
-0.15
1600
23
28
0.063
0.606
100.2
0.25
-0.05
1600
21
26
0.063
0.606
100.2
0.25
0.05
1600
21
26
02 CO C02 HC
(PCT) (PCT) (PCT) (PPM)
0
c
0
0
0
0
0
0
0
c
0
0
0
0
0
0
0
0
0
0
c
0
0
1.50
0.573
9.19
1.40
0.599
9.19
1.40
0.546
9. 19
1.40
0.573
9.08
1.30
0.653
9.08
1.10
0.816
9.19
1.10
0.844
9.19
1.10
C.816
9.19
1.10
0.844
9.29
1. 10
0.872
9.C8
1.00
0.789
9.29
1.00
0.816
9.29
0.97
0.872
9. 19
0.96
0.872
9. 19
0.97
0.899
9.19
0.97
0.844
9.29
C.99
0.844
9.29
C.98
0.816
9.29
0.97
0.816
9.08
0.98
0.816
9. 19
1.10
0.789
9. 19
1.00
0.844
9.19
0.99
0.816
9.29
-------
RUN NUMBER 344
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL
AIR
PCT
AXIAL
RADIAL
WALL
NO
NOX
FLOW
FLOW
STOIC
CIST
01 ST
TEMP
(CFM)
(CFM)
AIR
(IN)
( IN)
(C)
(PPM)
(PPM)
0.123
0.606
51.6
1.00
O.OC
1600
1
2
0.123
0.606
51.6
1.00
o.oc
1600
1
2
0.123
0.606
51.6
1.00
0.00
1600
1
0.109
0.606
58.3
1.00
0.00
1600
1
2
0.109
0.606
58.3
1.00
0.00
1600
1
2
0.116
0.606
54.8
1.00
O.OC
1600
1
0.116
0.606
54.8
1.00
0.00
16C0
1
0.123
0.606
51.6
I.00
O.OC
1600
1
0.123
0.606
51.6
1.00
o.oc
16C0
1
0.109
0.606
58.3
l.CO
O.OC
1600
1
0.109
0.606
58.3
l.CO
-0.1C
1600
1
0.109
0.606
58.3
1.00
C.1C
1600
1
0.109
0.606
58.3
l.CO
C.2C
1600
1
0.109
0.606
58.3
I.00
-C.2C
1600
1
0.109
0.606
58.3
1.00
0.00
1600
1
0.045
0.606
139.3
I.00
0.00
1600
7
10
0.057
0.606
110.8
1.00
0.00
1600
18
26
0.063
0.606
ICO.2
1.00
0.00
1600
30
35
0.069
0.606
91.3
1.00
0.00
1600
37
0.076
0.606
83.7
1.00
O.OC
1600
34
0.082
0.606
77.2
1.00
O.OC
1600
24
0.088
0.606
71.6
1.00
O.OC
1600
4
0.095
0.606
66.6
1.00
O.OC
1600
1
02 CO C02 HC
(PCT) (PCT ) (PCT) (PPM)
2
2
1
I
1
2
3
3
2
3
3
3
3
4
4
5
6
6
5
6
6
6
6
6.00
5.412
2.37
7.40
4.158
1.98
8.50
3.403
1.79
4.20
6.134
3.15
4.50
5.984
3.05
5.40
5.551
2.66
5.90
5.412
2.56
6.60
4.882
2.17
7.40
4.274
1.98
4.60
5.837
2.85
4.40
5.837
2.85
4.60
5.837
2.85
4.50
5.693
2.85
4.40
5.984
2.85
5.20
5.412
2.66
5.00
0.079
7.21
2.20
0.206
8.77
1.10
0.816
9.08
0.82
2.681
8.25
0.79
4.274
7.10
C.83
5.693
6.07
1.30
6.603
5.15
2.30
6.765
4.14
-------
RUN NUFBER 344 CONT
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.109
0.606
58.3
0.75
-0.1C
1600
1
0.109
0.606
58.3
0.75
0.1C
1600
1
0.109
0.606
58.3
0.75
C.2C
1600
1
0.109
0.606
58.3
0.75
-0.2C
16C0
1
0.109
0.606
58.3
0.50
0.00
1600
1
0.109
0.606
58.3
0.50
-0.10
1600
1
2
0.109
0.606
58.3
0.50
0.10
1600
1
2
0.109
0.606
58.3
0.50
0.20
1600
1
2
0.109
0.606
58.3
0.50
-0.20
1600
0
3
0.109
0.606
58.3
0.25
O.OC
1600
0
3
0.109
0.606
58.3
0.25
O.OC
1600
c
1
C 2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
5.30
5.551
2.76
5.50
5.412
2.66
5.10
5.551
2.76
5.60
5.27fe
2.56
6.30
A.882
2.46
6.80
4.632
2.27
7.00
4.510
2.37
6.60
4.632
2.37
7.80
4.158
2.17
7.90
4.882
2.85
10.70
2.817
2.27
9
9
9
8
10
11
10
10
11
0
0
-------
RUN NUMBER 347
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR PCT AXIAL RADIAL WALL NO NOX
FLOW FLOW STOIC DIST DIST TEMP
ICFMl (CFM) AIR (IN) (INI (C) (PPM) (PPM)
0.063
0.606
100.2
1.00
O.OC
1450
24
3C
0.067
0.606
94.7
1.00
O.OC
1450
34
0.069
0.606
91.3
1.00
0.00
1450
37
0.073
0.606
86.6
1.00
0.00
1450
38
0.076
0.606
83.7
1.00
0.00
1450
38
0.082
0.606
77.2
1.00
0.00
1450
27
0.088
0.606
71.6
1.00
O.OC
1450
13
0.095
0.606
66.6
1.00
O.OC
1450
1
5
0.102
0.606
62.2
1.00
O.OC
1450
0
3
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
1.20
0.335
9.19
0.82
1.269
8.87
0.79
2.135
8.46
0.81
2.824
8.04
0.84
3.716
7.42
0.88
5.276
6.38
1.20
6.444
5.25
2.50
6.765
4.34
6.60
5.142
3.05
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 349
AO IABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.017
0.594
141.9
0. 15
0.00
1600
8
11
0.017
0.594
141.9
0.15
-0.08
1600
8
11
0.017
0.594
141.9
0.15
-0.15
1600
7
11
0.017
0.594
141.9
0.15
-0.23
1600
7
10
0.017
0.594
141.9
0.15
-0.3C
1600
8
11
0.017
0.594
141.9
0.15
0.08
16C0
9
12
0.017
0.594
141.9
0.15
C.15
1600
9
12
0.017
0.594
141.9
0.15
0.23
1600
8
11
0.017
0.594
141.9
0.15
0.30
1600
8
11
0.017
0.594
141.9
0.05
0.00
1600
9
12
0.017
0.594
141.9
0.05
-0.08
1600
9
12
0.017
0.594
141.9
0.05
-0.15
1600
8
11
0.017
0.594
141.9
0.05
-0.23
1600
8
11
0.017
0.594
141.9
0.05
-0.30
1600
7
10
0.017
0.594
141.9
0.05
0.08
1600
8
10
0.017
0.594
141.9
0.05
0.15
1600
7
10
0.017
0.594
141.9
0.05
0.23
1600
8
10
0.017
0.594
141.9
0.05
0.3C
16C0
7
1C
0.017
0.594
141.9
0.25
O.OC
16C0
7
9
0.017
0.594
141.9
0.25
-0.15
1600
7
9
0.017
0.594
141.9
0.25
-C.3C
1600
6
8
0.017
0.594
141.9
0.25
C.15
1600
7
9
0.017
0.594
141.9
0.25
0.30
1600
6
8
C 2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
8.30
8. AO
8.50
8.40
8.20
8.20
8.40
8.30
8.30
8.20
7.90
8.10
8.00
8.20
8.20
8.10
8.10
8.00
e.ic
8.00
8.00
8.10
8.00
0.000
0.000
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OOC
O.OCC
O.OOC
O.OOC
O.OOC
7.10
7.00
6.90
6.79
7.CO
7.CO
6.90
6.90
6.90
6.79
6.79
6.69
6.59
6.48
6.48
6.59
6.59
6.59
6.59
6.59
6.69
6.59
6.59
5
0
0
0
C
0
0
0
0
0
0
0
0
0
0
0
0
0
0
C
C
0
0
-------
RUN NUMBER 350
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE
HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
DIST
(IN)
RAOIAL
DIST
(IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
(PPM)
0.017
0.594
141.9
0.50
O.OC
1600
4
6
0.017
0.594
141.9
0.50
-0.15
1600
4
6
0.017
0.594
141.9
0.50
-0.30
1600
4
6
0.017
0.594
141.9
0.50
0.15
1600
5
7
0.017
0.594
141.9
0.50
0.3C
1600
4
6
0.017
0.594
141.9
0.75
O.OC
1600
4
6
0.017
0.594
141.9
0.75
-0.15
1600
4
6
0.017
0.594
141.9
0.75
-0.30
1600
4
6
0.017
0.594
141.9
0.75
0.15
1600
5
7
0.017
0.594
141.9
0.75
0.30
1600
4
6
0.017
0.594
141.9
l.CO
0.00
1600
4
6
0.017
0.594
141.9
1.00
-0.15
1600
4
6
0.017
0.594
141.9
1.00
-0.30
1600
5
7
0.017
0.594
141.9
1.00
0.15
1600
5
7
0.017
0.594
141.9
1.00
0.30
1600
4
6
0.017
0.594
141.9
2.00
0.00
1600
7
9
0.017
0.594
141.9
3.00
0.00
1600
9
11
0.017
0.594
141.9
4.00
0.00
1600
10
12
0.017
0.594
141.9
5.00
0.00
1600
11
13
0.017
0.594
141.9
6.00
0.00
1600
12
14
0.017
0.594
141.9
0.05
O.OC
16C0
5
7
0.017
0.594
141.9
-0.05
-0.15
1600
4
6
0.017
0.594
141.9
0.05
-0.30
1600
4
6
G2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
9.60
O.OOC
6.59
9.60
0.000
6.69
9.60
0.000
6.59
9.90
0.000
6.48
9.70
O.OOC
6.48
9.60
O.OCC
6.59
S.60
C.OCC
6.48
9.40
O.OOC
6.69
9.40
O.OOC
6.69
9.20
O.OOC
6.69
9.40
0.000
6.69
9.20
O.OOC
6.59
9.40
O.OCC
6.59
9.60
O.OOC
6.48
9.50
O.OOC
6.38
8.10
0.000
7.31
8.10
O.OOC
7.31
8.00
O.OOC
7.21
8.10
O.OOC
7.00
8.10
O.OOC
7.10
7.90
O.OOC
7.31
8.00
O.OCC
7.31
7.90
O.OOC
7.21
0
0
0
0
0
0
0
0
0
0
0
0
0
c
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 350 CONT
ADIABATIC STIRRED COMBUSTGR
NORMAL COMBUSTION
PROPANE
HOT HALL
FUEL
FLOW
CCFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
DIST
(IN)
RADIAL
DIST
(IN)
WALL
TEMP
(C)
NO
NOX
(PPM) (PPM)
0.017
0.594
141.9
0.05
0.15
1600
4
6
0.017
0.594
141.9
0.05
0.3C
1600
4
5
0.022
0.594
112.4
0.05
C.OC
1600
6
e
0.022
0.594
112.4
0.05
-0.15
1600
6
9
0.022
0.594
112.4
0.05
-0.30
1600
7
9
0.022
0.594
112.4
0.05
0.15
1600
7
9
0.0 22
0.594
112.4
0.05
0.3C
1600
6
9
C2
(PCT)
CO
(PCT)
CO 2
(PCT)
HC
(PPM)
8.00
O.OOC
7.31
7.80
O.OOC
7.21
4.00
0.000
9.60
4.20
O.OOC
9.50
4.10
O.OOC
9.50
4.20
O.OOC
9.39
4.50
0.028
9.29
0
0
0
0
0
0
0
-------
RUN NUMBER 351
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL
AIR
PCT
AXIAL
RADIAL
WALL
NO
NOX
FLOW
FLOW
STOIC
01 ST
OIST
TEMP
(CFM)
(CFM)
AIR
(IN)
( IN)
(C)
(PPM)
(PPM)
O.Oll
0.594
219.1
3.20
o.oc
1600
2
4
0.011
0.438
161.7
3.20
o.oc
1600
6
9
0.031
0.678
90.8
3.20
o.oc
16C0
41
42
0.024
0.678
117.3
3.20
0.00
1600
17
23
0.017
0.678
161.8
3.20
o.oc
1600
5
8
0.011
0.678
249.9
3.20
0.00
1600
3
5
0.005
0.678
498.7
3.20
o.oc
1600
1
3
C2
CO
CO 2
HC
(PCT)
(PCT)
(PCT)
(PPM)
14.00
O.OOC
4.55
0
10.50
O.OOC
6.28
0
1.45
2.2C1
9.50
0
4.80
O.OOC
9.39
0
9.70
O.OCC
6.90
0
14.40
O.OOC
4.34
0
20.00
0.206
1.31
1600
-------
RUN NUMBER 352*
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HCT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RAO IAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.012
0.67 8
226.1
3.20
o.oc
1600
3
4
0.015
0.678
189.1
3.20
o.oc
1600
3
5
0.017
0.678
161.8
3.20
0.00
1600
5
7
0.020
0.678
140.9
3.20
0.00
1600
9
11
0.022
0.678
124.3
3.20
0.00
1600
24
3C
0.024
0.678
114.1
3.20
o.oc
1600
43
53
0.027
0.678
105.2
3.20
o.oc
1600
19
26
0.029
0.678
97.5
3.20
o.oc
1600
38
42
0.031
0.678
90.8
3.20
o.oc
1600
44
45
0.035
0.678
79.5
3.20
o.oc
1600
46
46
0.038
0.678
73.3
3.20
o.oc
1600
46
0.035
0.678
79.5
3.20
-0.15
1600
44
44
0.035
0.678
79.5
3.20
-0.3C
1600
45
45
0.035
0.678
79.5
3.20
0.15
1600
44
44
0.035
0.678
79.5
3.20
0.30
1600
43
43
0.044
0.678
64.3
3.20
0.00
1600
18
0.046
0.678
61.1
3.20
0.00
1600
2
0.049
0.678
58.1
3.20
0.00
1600
1
0.050
0.678
56.3
3.20
0.00
1600
1
0.017
0.678
161.8
3.20
-0.15
1600
6
1C
0.017
C.678
161.8
3.20
-0.30
16C0
4
7
0.017
0.678
161.8
3.20
0.15
1600
5
7
0.017
0.678
161.8
3.20
0. 30
1600
4
6
* Air leak in sampling system amounting to 8X of total sampled volume.
C2 CO C02 hC
(PCT) (PCT) (PCT) (PPM)
13.90 O.OOC 4.55 0
12.30 O.OOC 5.25 0
10.70 O.OOC 6.07 C
8.60 O.OOC 7.10 0
6.20 O.OOC 8.35 0
5.00 O.OOC 8.87 0
3.AO 0.053 9.60 0
1.80 0.872 10.49 0
1.70 3.1C4 9.02 0
1.60 5.837 7.13 0
1.60 7.81C 6.21 0
1.60 5.984 7.36 0
1.55 5.837 7.13 0
1.50 5.984 7.36 0
1.50 5.984 7.36 0
1.45 7.448 5.53 400
1.40 9.626 5.08 7500
1.40 11.023 4.20 10000
1.40 11.023 4.20 18000
9.90 O.OOC 6.90 0
9.80 O.OCC 6.69 C
9.90 O.OOC 6.79 C
9.80 O.OOC 6.69 C
-------
RUN NUMBER 352*C0NT
ADIABATIC STIRREO COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WAIL
FUEL AIR
FLOW FLOW
(CFM1 (CFM)
PCT AXIAL
STOIC OIST
AIR (IN)
RADIAL WALL
OIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.017 0.678
0.035 0.678
0.035 0.678
161.8 2.20
79.5 2.20
79.5 1.20
O.OG 1600
O.OC 1600
0.00 1600
3 6
A3 A3
AO
* Air leak in sampling system amounting to 8% of total sampled volume.
02
(PCT)
CO
(PCT)
9.90
1.50
l.AO
O.OOC
5.693
5.551
C02
(PCT)
HC
(PPM)
6.69
7.93
8 .1A
0
0
0
-------
RUN NUMBER 353*
AOIABATIC STIRRED CGM8USTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFMI (CFMJ
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.017
0.678
161.8
1.20
0.00
1600
4
6
0.017
0.678
161.8
1.00
O.OC
1600
4
6
0.017
0.678
161.8
1.00
-0.15
1600
4
6
0.017
0.678
161.8
1.00
-0.30
1600
4
5
0.017
0.678
161.8
1.00
0.15
1600
4
6
0.017
0.678
161.8
1.00
0.30
1600
4
6
0.035
0.678
79.5
1.00
O.OC
1600
38
39
0.035
0.678
79.5
1.00
-0.15
1600
37
38
0.035
0.678
79.5
1.00
-0.3C
1600
38
39
0.035
0.678
19.5
l.CO
0.15
16C0
36
37
0.035
0.678
79.5
1.00
0.3C
1600
39
4C
0.035
0.678
79.5
0.75
0.00
1600
40
-
0.035
0.678
79.5
0.75
-0.15
1600
41
-
0.035
0.678
79.5
0.75
-0.30
1600
41
-
0.035
0.678
79.5
0.75
0.15
1600
39
-
0.035
0.678
79.5
0.75
0.30
1600
40
-
0.017
0.678
161.8
0.75
0.00
1600
5
7
0.017
0.678
161.8
0.75
-0.15
1600
4
7
0.017
0.678
161.8
0.75
-0.30
1600
4
6
0.017
0.678
161.8
0.75
0.15
1600
4
6
0.017
0.678
161.8
0.75
0.30
1600
3
6
0.017
0.678
161.8
0.50
0.00
1600
3
6
0.017
0.678
161.8
0.50
-0.15
1600
3
5
* Air leak in sampling system amounting to 8% of sampled volume.
C2
CO
C02
(PCT)
(PCT)
(PCT)
10.70
o.02e
6.59
10.80
0.000
6.48
10.80
0.028
6.48
10.70
0.028
6.38
10.70
O.OOC
6.48
10.60
C.028
6.38
1.60
4.274
8.46
1.60
4.632
8.25
1.70
4.756
8.14
1.60
4.632
8.14
1.70
4.882
7.83
1.50
5.984
7.42
1.60
5.984
7.42
1.60
5.984
7.31
1.50
5.837
7.52
1.60
5.837
7.31
1C.40
0.028
6.59
1C.30
O.OOC
6.69
10.20
O.OCC
6.59
10.20
O.OOC
6.48
10.00
O.OOC
6.38
10.10
O.OOC
6.48
10.20
O.OOC
6.48
)
C
C
0
0
0
0
0
0
0
c
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 353*C0NT
AOIABATIC STIRRED COM0USTCR
NORMAL COMBUSTICN
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFMI (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.017
0.678
161.8
0.50
-0.30
1600
3
0.017
0.678
161.8
0.50
0.15
1600
4
0.017
0.678
161.8
0.50
0.30
1600
3
0.035
0.678
79.5
0.50
O.CC
1600
34
0.035
0.678
79.5
0.50
-0.15
1600
35
0.035
0.678
79.5
0.50
-0.30
1600
33
0.035
0.678
79.5
0.50
0.15
1600
33
0.035
0.678
79.5
0.50
0.30
1600
33
0.035
0.678
79.5
0.25
O.OC
16C0
29
0.035
0.678
79.5
0.25
-0.15
1600
30
0.035
0.678
79.5
0.25
-0.30
1600
29
0.035
0.678
79.5
0.25
0.15
1600
29
0.035
0.678
79.5
0.25
0.30
1600
28
0.017
0.678
161.8
0.25
0.00
1600
5
0.017
0.678
161.8
0.25
-0.15
1600
4
0.017
0.678
161.8
0.25
-0.3C
1600
5
0.017
0.678
161.8
0.25
0.15
1600
5
0.017
0.678
161.8
0.25
0.30
1600
5
* Air leak in sampling system amounting to 8Z of sampled volume.
C2
CO
CQ2
(PCT)
(PCT)
(PCT)
10.00
0.000
6.38
9.90
o.ooc
6.48
9.80
o.ooc
6.38
1.40
4.51C
8.14
1.30
4.756
8.04
1.40
4.632
8.C4
1.40
5.142
7.83
1.40
5.412
7.52
1.30
5.142
7.93
1.30
5.276
7.83
1.40
5.551
7.62
1.30
5.693
7.62
1.30
5.693
7.52
1C.OO
0.028
6.69
9.70
O.OOC
6.79
9.50
0.028
6.79
9.50
O.OOC
6.90
9.40
O.OOC
6.69
)
0
0
0
0
0
c
0
0
0
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 354*
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
ICFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0-017
0.678
161.8
0.C5
0.00
1600
4
6
0.017
0.678
161.8
0.05
-0.15
1600
3
4
0.017
0.678
161.8
0.05
-0.30
1600
3
5
0.017
0.678
161.8
0.05
0.15
1600
4
fc
0.017
0.678
161.8
0.05
0.30
1600
4
5
0.035
0.678
79.5
0.05
O.OC
1600
36
-
0.035
0.678
79.5
0.05
-0.15
1600
37
-
0.035
0.678
79.5
0.05
-0.3C
1600
38
-
0.035
0.678
79.5
0.05
0.15
1600
36
-
0.035
0.678
79.5
0.05
0.3C
1600
37
—
0.012
0.678
226.1
0.05
0.00
1600
0
2
0.015
0.678
189.1
0.05
O.OC
1600
0
3
0.017
0.678
161.8
0.05
O.OC
1600
4
7
0.020
0.678
140.9
0.05
0.00
1600
8
11
0.022
0.678
124.3
0.05
0.00
1600
26
36
0.024
0.678
114.1
0.05
0.00
1600
9
14
0.027
0.678
105.2
0.05
0.00
1600
16
22
0.029
0.678
97.5
0.05
0.00
1600
29
32
0.031
0.678
90.8
0.05
O.OC
1600
34
35
0.035
0.678
79.5
0.05
0.00
1600
37
-
0.038
0.678
73.3
0.05
O.OC
1600
35
-
0.041
0.678
67.9
0.05
O.OC
1600
26
-
* Air leak in sampling system amounting to 5% of sampled volume.
02
CO
C02
HC
(PCT)
(PCT)
(PCT)
(PPM)
9.60
0.028
6.69
5
9.50
0.053
6.79
3C
9.40
0.053
6.69
10
9.40
0.028
6.79
0
9.30
0.028
6.59
0
1.10
5.011
8.46
0
1.20
5.412
6.14
0
1.20
5.276
8.04
0
1.10
5.142
8.25
C
1.20
4.756
8.25
0
14.60
C.44C
3.94
6800
11.80
0.155
5.46
1000
9.30
0.026
6.90
10
7.80
0.053
7.52
0
5.40
0.129
8.66
0
4.50
0.104
9.29
0
2.50
0.129
10.49
0
1.20
1.24C
10.73
0
1.10
3.506
9.19
0
1.10
4.882
8.25
0
1.10
6.765
7.21
10
1.10
9.4C8
5.46
3500
-------
RUN NUMBER 355*
ADIABATIC STIRREO COMBUSTOR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
CCFMI (CFM >
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.020
0.678
140.9
0.25
-0.30
1600
7
9
0.020
0.678
140.9
0.25
-0.15
16C0
8
11
0.020
0.678
140.9
0.50
-0.15
1600
9
12
0.020
0.678
140.9
0.50
-0.3C
1600
8
12
0.020
0.678
140.9
0.75
-0.30
1600
8
12
0.020
0.678
140.9
0.75
-0.15
1600
10
13
0.020
0.678
140.9
1.00
-0.15
1600
10
13
0.020
0.678
140.9
1.00
-0.30
1600
9
13
0.024
0.678
114.1
0.25
-0.3C
1600
10
15
0.024
0.678
114.1
0.25
-0.15
1600
10
15
0.024
0.678
114.1
0.50
-0.15
1600
11
16
0.024
0.678
114.1
0.50
-0.30
1600
12
16
0.024
0.678
114.1
0.75
-C.3C
1600
11
15
0.024
0.678
114.1
0.75
-0.15
1600
12
17
0.024
0.678
114.1
1.00
-0.15
1600
12
lfc
* Air leak in sampling system amounting to 5X of sampled volume.
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
8.10
0.028
7.31
8.10
C.028
7.42
7.90
0.000
7.52
7.80
0.028
7.42
7.80
0.028
7.42
7.90
O.OOC
7.52
7.80
O.OOC
7.52
7.80
O.OOC
7.42
4.30
0.181
9.29
4.40
0.155
9.29
4.30
0.129
9.39
4.20
0.155
9.29
4.20
0.155
9. 19
4.10
0.104
9.39
4.20
0.079
9.39
0
0
0
0
0
0
0
0
0
0
c
c
0
0
0
-------
RUN NUMBER 355*C0NT
ADIABATIC STIRRED CGM8UST0R
NORMAL COMBUST ION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.024
0.678
114.1
1.00
-0.30
1600
11
16
0.027
0.678
105.2
0.25
-0.30
1600
15
25
0.027
0.678
105.2
0.25
-0.15
1600
14
24
0.027
0.678
105.2
0.50
-0.15
1600
16
26
0.027
0.678
105.2
0.50
-0.30
1600
14
25
0.027
0.678
105.2
0.75
-0.3C
1600
16
26
0.027
0.678
1G5.2
0.75
-0.15
1600
17
26
0.027
0.678
105.2
1.00
-0.15
16C0
19
26
0.027
0.678
105.2
1.00
-0.30
1600
19
28
0.029
0.678
97.5
0.25
-0.30
1600
29
34
0.029
0.678
97.5
0.25
-C.15
1600
25
31
0.029
0.678
97.5
0.50
-0.15
1600
26
32
0.029
0.678
97.5
0.50
-0.30
1600
26
32
0.029
0.678
97.5
0.75
-0.30
1600
30
34
0.029
0.678
97.5
0.75
-0.15
1600
32
35
0.029
0.678
97.5
1.00
-0.15
1600
32
34
0.029
0.678
97.5
1.00
-0.3C
1600
32
35
0.031
0.678
90.8
0.25
-0.30
1600
32
33
0.031
0.678
90.8
0.25
-0.15
1600
29
30
0.031
0.678
90.8
0.50
-0.15
1600
31
32
0.031
0.678
90.8
0.50
-C.3C
1600
32
33
0.031
0.678
90.8
0.75
-0.30
1600
33
34
0.031
0.678
90.8
0.75
-0.15
1600
34
36
* Air leak in sampling system amounting to 5X of sampled volume.
G2
< PCT}
CO
(PCT)
C02
(PCT)
hC
(PPM)
4.30
0.IC4
9.19
2.10
0.309
9.71
2.10
0.361
10.49
2.10
0.361
10.73
2.40
C.3C9
9.92
2.50
0.283
9.92
2.20
C.2C6
10.73
2.20
0.283
10.49
2.10
0.335
10.49
1.00
1.096
10.49
1.10
0.734
11.23
1.00
0.707
10.98
1.00
1.068
10.73
1.10
1.476
10.49
0.90
1.506
10.49
0.90
1.567
10.49
1.00
1.659
10.49
0.82
2.681
9.60
0.79
2.681
9.71
0.81
2.788
9.60
C.83
2.752
9.39
0.90
2.933
9.39
0.90
2.912
9.50
0
0
0
0
c
0
€
0
C
C
0
0
0
0
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 355*C0NT
ADIABATIC STIRRED COMBUSTCR
NORMAL CGMBUST ION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFMI (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
01 ST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.031
0.678
90.8
1.00
-0.15
1600
36
-
0.031
0.678
90.8
1.00
-0.30
1600
36
-
0.035
0.678
79.5
0.25
-0 .30
1600
34
-
0.035
0.678
79.5
0.25
-0.15
1600
32
-
0.035
0.678
79.5
0.50
-0.15
1600
34
-
0.035
C .678
79.5
0.50
-0.3C
1600
36
-
0.035
0.678
79.5
0.75
-0.3C
1600
36
-
0.035
0.678
79.5
0.75
-0.15
1600
36
-
0.035
0.678
79.5
1.00
-C.15
1600
37
-
0.035
0.678
79.5
1.00
-0.30
1600
38
-
0.038
0.678
73.3
0.25
-0.30
1600
22
-
0.038
0.678
73.3
0.25
-0.15
1600
18
-
0.038
0.678
73.3
0.50
-0.15
1600
21
-
0.038
0.678
73.3
0.50
-0.30
1600
26
-
0.038
0.678
73.3
0.75
-0.30
1600
32
-
0.038
0.678
73.3
0.75
-0.15
1600
28
-
0.038
0.678
73.3
1.00
-0.15
1600
32
-
0.038
0.678
73.3
1.00
-0.3C
1600
35
-
* Air leak in sampling system amounting to 5% of sampled volume.
C2
CO
C02
hC
PCT)
(PCT)
(PCT)
(PPM)
0.92
3.007
9.39
0
0.92
3.007
9.19
0
C.84
5.693
7.62
0
0.80
5.693
7.83
0
C. 82
5.837
7.42
C
0.84
5.837
7.62
0
0.87
5.837
7.52
0
C. 84
5.837
7.62
0
0.83
5.984
7.52
0
0.86
5.984
7.52
0
0.81
7.627
6.59
920
C. 82
7.81C
6.69
1600
0.79
7.627
6.69
600
0.82
7.627
6.59
270
C.83
7.996
6.48
20
C.80
7.81C
6.69
240
0.80
7.996
6.69
5
0.80
7.996
6.38
C
-------
RUN NUMBER 356*
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE
HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
01 ST
(IN)
RADIAL
DIST
(IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
(PPM)
0.020
0.678
140.9
0.25
0.3C
1600
2
5
0.024
0.678
114.1
0.25
C.3C
1600
11
16
0.027
0.678
105.2
0.25
0.3C
1600
17
23
0.029
0.678
97.5
0.25
0.30
1600
25
29
0.031
0.678
90.8
0.25
0.30
1600
29
31
0.035
0.678
79.5
0.25
0.30
1600
34
-
0.036
0.678
73.3
0.25
0.30
16C0
29
-
0.020
0.678
140.9
0.25
0.00
1600
1
5
0.020
0.678
140.9
0.50
O.OC
16C0
3
6
0.020
0.678
140.9
0.75
O.OC
16C0
4
7
0.C20
0.678
140.9
1.00
O.OC
16C0
5
8
0.022
C.678
124.3
0.25
O.OC
1600
6
11
0.022
0.678
124.3
0.50
0.00
1600
8
13
0.022
0.678
124.3
0.75
0.00
1600
10
17
0.022
0.678
124.3
1.00
0.00
1600
13
19
0.024
0.678
114.1
0.25
0.00
1600
9
13
0.024
0.678
114.1
0.50
0.00
1600
9
13
0.024
0.678
114.1
0.75
0.00
1600
10
14
0.024
0.678
114.1
1.00
O.OC
16C0
11
15
0.027
0.678
IC5.2
0.25
O.OC
1600
15
21
0.027
0.678
ICS.2
0.50
0.00
16C0
14
21
0.027
0.678
105.2
0.75
O.OC
16C0
15
22
* Air leak in sampling system amounting to 4Z of sampled volume.
C2
CO
C02
HC
PCT)
(PCT)
(PCT)
(PPM)
7.50
O.OCC
7.62
15
3.70
0.000
9.39
0
2.20
0.028
10.49
0
1.00
0.546
10.73
0
0.86
3.007
9.29
0
0.84
5.837
7.62
0
0.82
7.627
6.59
220
8.30
0.155
7.00
650
8.20
C .028
7.21
50
8.10
O.OOC
7.31
5
8.10
O.OCC
7.31
5
5.50
0.053
8.66
30
5.60
0.028
8.77
5
5.60
0.028
8.66
0
5.70
0.028
8.56
0
3.90
O.OOC
9.50
C
4. 10
O.OCC
9.39
0
4.10
O.OOC
9.39
0
3.90
O.OOC
9.50
C
2.60
C.053
10.49
C
2.70
0 .079
4.55
0
2.60
0.104
4.55
0
-------
RUN NUMBER 356*C0NT
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE
HCT MALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
DI ST
(IN)
RAOIAL
01 ST
( IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
I PPM)
0.027
0.678
105.2
1.00
o.cc
1600
15
0.029
0.678
97.5
0.25
c.oc
16CC
28
0.029
0.678
97.5
0.50
c.oc
1600
28
0.029
0.678
97.5
0.75
o.oc
1600
28
0.029
0.678
97.5
1.00
0.00
1600
29
0.031
0.678
90.8
0.25
0.00
1600
28
0.031
0.678
90.8
0.50
0.00
1600
29
0.031
0.678
9C.8
0.75
o.oc
1600
31
0.031
0.678
90.8
1.00
0.00
16C0
32
0.035
0.678
79.5
C.25
o.oc
1600
31
0.035
0.678
79.5
0.50
c.oc
1600
33
0.035
0.678
79.5
0.75
c.oc
1600
34
0.035
0.678
79.5
l.CO
o.oc
16C0
35
0.038
0.678
73.3
0.25
0.00
1600
28
0.038
0.678
73.3
0.50
0.00
1600
29
0.038
0.678
73.3
0.75
0.00
1600
31
0.038
0.678
73.3
1.00
0.00
1600
33
0.020
0.678
140.9
0.05
0.3C
1600
3
0.020
0.678
140.9
0.05
0.15
1600
4
0.020
0.678
140.9
0.25
0.15
1600
4
0.020
0.678
140.9
0.50
0.3C
1600
5
0.020
0.678
140.9
0.50
0.15
1600
4
0.020
0.678
140.9
0.75
0.15
1600
4
22
31
30
30
31
* Air leak in sampling system amounting to 4% of sampled volume.
C2
CO
C02
HC
PCT)
(PCT)
(PCT)
(PPM)
2.50
C. 129
10.49
C
C . 89
C.927
10.98
C
0.86
0.844
11.23
0
0.90
0.899
11.23
C
0.93
0.983
10.98
0
0.75
3.104
9.50
0
C.76
3.104
9.50
0
C.78
3. 203
9.39
0
C . 80
3.302
9.29
0
C.72
5.837
7.93
C
0.74
5.693
7.93
C
0.76
5.837
7.63
0
C.79
5.984
7.73
0
0.72
7.996
6.69
140
0.71
7.996
6.69
100
C. 75
7.996
6.59
70
0.77
7.996
6.59
25
7.60
O.OCC
7.52
15
7.8C
O.OCC
7.62
1C
7.70
O.OCC
7.73
5
7.6C
O.OCC
7.52
0
7.80
O.OOC
7.73
0
7.80
O.OOC
7.62
0
-------
RUN NUMBER 356*C0NT
A01ABATIC STIRREO COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM|
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
01 ST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.020
0.678
140.9
0.75
0.3C
1600
4
7
0.020
0.678
140.9
1.00
0.30
1600
5
7
0.020
0.678
140.9
1.00
0.15
1600
5
8
0.024
0.678
114.1
0.05
0.30
1600
9
13
0.024
0.678
114.1
0.05
0.15
16CC
9
13
0.024
0.678
114.1
0.25
0.15
1600
10
14
0.024
0.678
114.1
C. 50
0.3C
1600
11
14
0.024
0.678
114.1
0.50
C. 15
1600
10
14
0.024
0.678
114.1
0.75
C. 15
16C0
10
14
0.024
0.678
114.1
0.75
0.30
1600
11
14
0.024
0.678
114.1
1.00
0.30
1600
11
15
0.024
0.678
114.1
1.00
0.15
1600
12
16
* Air leak in sampling system amounting to 4Z of sampled volume.
02
CO
C02
PCT)
(PCT)
(PCT)
7.70
o.ooc
7.42
7.80
0.000
7.42
7.80
o.ooc
7.52
3.90
o.ooc
9.29
4.00
O.OCC
9.39
4.00
C.OCC
9.60
4.10
O.OCC
9.29
4.20
0.000
9.50
4.20
O.OOC
9.50
3.90
O.OOC
9.50
3.90
o.ooc
9.50
4.00
o.ooc
9.60
)
0
0
0
0
0
0
0
0
0
0
0
0
-------
RUN NUMBER 357
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.027 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.029 0.678
0.031 0.678
0.031 0.678
0.031 0.678
0.031 0.678
105.2 0.05
105.2 0.05
105.2 0.25
105.2 0.50
105.2 0.50
105.2 0.75
1C5.2 0.75
1C5.2 1.00
105.2 l.CO
97.5 0.05
97.5 0.05
97.5 0.25
97.5 0.50
97.5 0.50
97.5 0.75
97.5 0.75
97.5 l.CO
97.5 1.00
90.8 0.05
90.8 0.05
90.8 0.25
90.8 0.50
0.30 1600
0.15 1600
0.15 1600
0.3C 1600
0.15 1600
0.15 16C0
C.3C 1600
0.3C 1600
0.15 1600
C.3C 1600
0.15 1600
0.15 1600
0.30 1600
0.15 1600
0.15 1600
0.30 1600
0.30 1600
C.15 1600
0.30 16C0
0.15 1600
0.15 1600
0.30 1600
16
22
16
23
17
23
18
24
17
23
16
22
17
23
17
23
16
23
26
29
25
28
26
28
26
27
27
28
27
29
26
28
27
29
27
29
29
30
28
29
27
28
28
28
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM )
2.40
0.07S
10.24
2.30
0.053
10.49
2.20
0.028
10.73
2.30
O.OOC
10.49
2.AO
0.028
10.73
2.AD
O.OCC
10.73
2.30
C. 028
10.49
2.50
C. 053
10.49
2.50
0.053
10.73
C. 78
0.872
10.73
0.80
0.816
10.98
0.76
0.789
11.23
0.78
0.844
10.98
0.74
0.816
10.98
C.80
0.844
11.23
0.82
0.872
10.98
0.83
C .899
10.98
0.80
0.899
11.23
0.73
3.007
9.39
0.71
3.104
9.50
0.70
3.104
9.60
0.73
3.104
9.39
0
0
0
0
0
0
c
c
0
0
0
0
0
0
0
0
0
c
0
0
0
0
-------
RUN NUMBER 358
ADIABATIC STIRRED COMBUSTOR
NORMAL COMBUST ION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RAOIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.031
0.678
90.8
0.50
0.15
1600
29
-
0.031
0.678
90.8
0.75
0.15
1600
29
-
0.031
0.678
90.8
0.75
0.30
1600
30
-
0.031
0.678
90.8
l.CO
C.3C
1600
29
-
0.031
0.678
90.8
l.CO
0.15
16C0
31
-
0.035
C .678
79.5
0.05
C.3C
1600
37
-
0.035
0.678
79.5
0.05
0.15
16C0
36
-
0.035
0.678
79.5
0.25
0.15
1600
36
-
0.035
0.678
79.5
0.50
0.30
1600
35
-
0.035
0.678
79.5
0.50
0.15
1600
35
-
0.035
0.678
79.5
0.75
0.15
1600
36
-
0.035
0.678
79.5
0.75
0.30
1600
34
-
0.035
0.678
79.5
1.00
0.3C
1600
35
-
0.035
0.678
79.5
l.CO
0.15
1600
36
-
0.038
0.678
73.3
0.05
0.30
1600
33
-
0.038
0.678
73.3
0.05
0.15
1600
31
-
0.038
C.678
73.3
C.25
0.15
1600
31
-
0.038
0.678
73.3
0.50
C.3C
16CC
32
-
0.036
0.678
73.3
0.50
0.15
1600
32
-
0.038
0.678
73.3
0.75
0.15
1600
32
-
0.038
0.678
73.3
0.75
0.30
1600
31
-
0.038
0.678
73.3
1.00
0.30
1600
33
-
0.038
0.678
73.3
1.00
0.15
1600
32
-
C2
CO
CC2
HC
PCT)
(PCT)
(PCT)
(PPM)
0.69
3.203
9.39
0
0.74
3.302
9.29
0
0.76
3.302
9.08
0
C . 77
3.403
8.98
0
C.76
3.403
9.08
0
0.74
5.837
7.42
0
C . 72
5.984
7.52
0
0.68
6.134
7.52
0
C. 72
5.984
7.42
0
0.67
6.134
7.62
0
0.70
6.134
7.62
0
0.67
5.984
7.31
0
0.68
6.134
7.31
0
C .66
6.134
7.52
0
C .66
7.448
6.48
160
C.67
7.448
6.59
250
C .65
7.627
6.69
130
C .66
7.448
6.48
40
0.67
7.627
6.69
45
0.69
7.627
6.69
25
0.66
7.627
6.59
30
0.70
7.810
6.38
5
0.67
7.810
6.59
25
-------
RUN NUMBER 358 CONT
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR PCT AXIAL RACIAL WALL NC NOX
FLOW FLOW STOIC DIST DIST TEMP
(CFM) (CFM) AIR (IN) (IN) (C> (PPM) (PPM)
0.020
0.678
140.9
0.05
-0.15
1600
5
7
0.020
0.678
140.9
0.05
-0.3C
1600
4
7
0.024
0.678
114.1
0.05
-0.15
1600
10
13
0.024
0.678
114.1
0.C5
-C.3C
16C0
9
13
0.027
0.678
105.2
0.05
-0.3C
1600
14
2C
0.027
0.678
1C5.2
0.05
-0.15
1600
15
22
0.029
0.678
97.5
0.C5
-0.15
1600
25
31
0.029
0.678
97.5
0.05
-0.30
1600
24
29
0.031
0.678
90.8
0.C5
-0.3C
1600
31
34
0.031
0.678
90.8
0.05
-0.15
1600
30
32
0.035
0.678
79.5
0.05
-0.15
1600
35
-
0.035
0.678
79.5
0.05
-0.30
1600
34
-
0.038
0.678
73.3
0.05
-0.3C
1600
31
-
0.038
0.678
73.3
0.05
-0.15
1600
30
-
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
7.50
O.OOC
7.62
7.40
0.000
7.62
4.30
O.OOC
9. 19
4.30
O.OOC
9.08
2.30
C.1C4
10.24
2.30
C.079
10.49
l.OC
0.414
10.98
1.10
0.414
10.73
0.70
2.541
9.39
0.69
2.817
9.50
0.66
5.551
7.73
0.66
5.412
7.73
C .65
7.272
6.79
0.64
7.272
6.79
0
0
0
0
0
0
C
0
0
0
0
0
90
45
-------
RUN NUMBER 359
AOIABATIC STIRRED COMBUSTCR
NORMAL CCWBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLCW
(CFM) (CFM)
PCT AXIAL
STOIC OIST
AIR (IN)
RACIAL WALL
DIST TEMP
(IN) (C)
NC NOX
(PPM) (PPM)
0.000
0.678
*****
I.CO
0.00
1800
120
-
0.029
0.678
97.5
1.00
o.oc
18C0
36
37
0.031
0.678
90.8
l.CO
o.oc
18C0
38
-
0.035
0.678
79.5
1.00
o.oc
1800
41
-
0.038
0.678
73.3
1.00
o.oc
18CC
AC
-
0.041
0.678
67.9
1.00
o.oc
1800
16
-
0.000
0.678
*****
1.00
0.00
1800
80
90
C2
CO
C02
HC
(PCT)
(PCT)
(PCT)
(PPM)
2C.80
O.OOC
0.00
0
C.75
1.269
10.49
0
C.69
3.0C7
9.19
0
C .66
6.134
7.42
C
C.65
7.627
6.59
C
C.66
9.194
5.56
1600
20.80
O.OOC
0.00
0
-------
RUN NUMBER 360
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) CCFM)
0.000 0.678
0.029 0.678
0.031 0.678
0.035 0.678
0.038 0.678
0.041 0.678
0.000 0.678
0.000 0.678
0.029 0.678
0.031 0.678
0.035 0.678
0.038 0.678
0.041 0.678
0.000 0.678
0.000 0.678
0.029 0.678
0.031 0.678
0.035 0.678
0.038 0.678
0.041 0.678
0.000 0.678
0.000 0.678
0.029 0.678
PCT AXIAL
STOIC DIST
AIR (IN)
***** 0.75
97.5 0.75
90.8 0.75
79.5 0.75
73.3 0.75
67.9 0.75
***** 0.75
***** 0.50
97.5 0.50
90.8 0.50
79.5 0.50
73.3 0.50
67.9 0.50
***** 0.50
***** 0.25
97.5 0.25
90.8 0.25
79.5 0.25
73.3 0.25
67.9 0.25
***** 0.25
***** 0.05
97.5 0.05
RADIAL WALL
DIST TEMP
(IN) (C)
0.00 1800
0.00 1800
0.00 1800
O.OC 1800
O.OC 18C0
O.OC 18C0
O.OC 1800
O.OC 1800
0.00 1800
O.OC 1800
O.OC 1800
0.00 18C0
O.OC 18C0
O.OC 1800
O.CO 1800
0.00 1800
0.00 1800
0.00 1800
O.OC 1800
0.00 1800
O.GC 1800
O.OC 1800
O.OC 18C0
NO NOX
(PPM) (PPM)
115
-
38
40
39
-
41
-
36
-
13
-
95
IOC
100
-
38
39
38
-
39
-
35
-
10
-
110
115
115
115
37
39
36
-
38
-
32
-
4
-
115
12C
120
12C
35
38
C2
CO
C02
hC
(PCT)
(PCT)
(PCT)
(PPM)
20.80
O.OOC
O.CO
0
0.82
1.096
10.98
0
C.74
3.007
9.60
0
0.71
6.444
7.62
0
C.69
7.996
6.69
20
C.67
9.848
5.56
1600
20.80
O.OCC
O.CO
0
20.80
O.OOC
O.CO
0
0.81
0.983
10.98
0
0.71
3.104
9.60
0
C.67
6.287
7.73
0
0.66
8.186
6.59
30
C. 66
9.626
5.66
2300
20.80
O.OCC
0.00
C
20.80
O.OOC
0.00
0
0.75
0.844
11.23
0
0.70
3.104
9.60
0
C. 70
6.287
7.73
0
0.69
8.186
6.69
80
0.68
9.626
5.77
6700
20.80
O.OCC
O.CO
C
20.80
O.OOC
0.00
0
C. 75
0.68C
11.48
0
-------
RUN NUMBER 360 CONT
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
PROPANE HOT WALL
FUEL AIR PCT AXIAL RADIAL WALL NO NOX
FLOW FLOW STOIC DIST CIST TEMP
(CFM) {CF f > AIR (IN) (IN) (C) (PPM) (PPM)
0.031
0.678
90.8
0.05
O.OC
18C0
32
33
0.035
0.678
79.5
0.05
C.CC
1800
36
-
0.038
0.678
73.3
0.05
0.00
1800
28
-
0.041
0.678
67.9
0.05
0.00
1800
3
-
0.000
0.678
*****
0.05
0.00
1800
120
120
02
CO
C02
HC
(PCT)
(PCT)
(PCT)
(PPM)
C .68
3.007
9.81
0
C .66
6.134
7.93
0
0.67
8.186
6.79
260
0.67
9.626
5.77
7100
20.80
O.OOC
0.00
0
-------
RUN NUMBER 362*
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) CCFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL WALL
01 ST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.102
0.708
72.7
3.00
0.00
1600
41
—
0.116
0.708
64.0
3.00
O.OC
1600
2
-
0.130
0.708
57.0
3.00
0.00
1600
0
0
0.051
0.708
144.3
3.00
O.OC
1600
6
e
0.063
0.708
117.0
3.CO
O.OC
1600
14
16
0.076
0.708
97.8
3.CO
O.OC
1600
36
38
0.088
0.708
83.5
3.00
O.OC
16C0
43
-
0.051
0.708
144.3
l.CO
O.OC
16C0
4
5
0.063
0.708
117.0
1.00
O.OC
16C0
9
11
0.076
0.708
97.8
l.CO
O.OC
1600
26
29
0.088
0.708
83.5
1.00
0.00
1600
34
-
0.102
0.708
72.7
1.00
0.00
1600
15
-
0.116
0.708
64.0
1.00
O.OC
1600
1
6
0.130
0.708
57.0
1.00
O.OC
1600
0
3
0.051
0.708
144.3
0.75
0.00
1600
5
7
0.063
0.708
117.0
0.75
O.OC
1600
15
18
0.076
0.708
97.8
0.75
O.OC
16C0
36
38
0.088
0.708
83.5
0.75
O.OC
1600
38
-
0.102
0.708
72.7
0.75
O.OC
1600
41
-
0.116
0.708
64.0
0.75
O.OC
1600
1
-
0.051
0.708
144.3
0.50
O.OC
1600
5
6
0.063
0.708
117.0
0.50
0.00
1600
13
16
0.076
0.708
97.8
0.50
0.00
1600
33
34
* Air leak in sampling system amounting to 4Z of sampled volume.
C2 CO CC2 hC
(PCT) (PCT) (PCT) (PPM)
5
2300
14000
0
0
0
0
0
0
0
0
4000
46000
74000
0
0
0
0
70
12000
5
0
0
0.82
7.448
4.85
0.79
8.985
4.14
0.79
9.408
3.74
7.20
0.053
6.69
4.00
0.1C4
7.83
1.10
1.328
8.46
C.87
4.756
6.28
7.20
0.079
6.59
4.10
0.155
7.73
1.20
1.357
8.25
0.88
4.51C
6.48
1.30
7.272
4.95
2.80
6.287
3.25
7.70
5.412
2.56
fc.90
0.053
6.59
3.80
0.1C4
7.93
1.00
1.125
8.56
C . 79
4.632
6.59
C.77
7.272
5.05
1.20
8.38C
4.14
7.20
1.877
C. 20
3.80
2.302
0.29
1.00
2.541
3.44
-------
RUN NUMBER 362*CQNT
ADIABATIC STIRRED CCMBUSTOR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PC T AXIAL
STOIC DIST
AIR (IN)
RADIAL WALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.088
0.708
83.5
0.50
O.OC
1600
36
-
0.102
0.708
72.7
0.50
0.00
1600
38
-
0.116
0.708
64.0
0.50
0.00
1600
0
0
0.051
0.708
144.3
0.25
0.00
1600
5
7
0.063
0.708
117.0
0.25
O.OC
1600
12
15
0.076
0.708
97.8
0.25
O.OC
16C0
30
32
0.088
0.708
83.5
0.25
O.OC
16C0
35
-
0.102
0.708
72.7
0.25
O.OC
1600
30
-
0.116
0.708
64.0
0.25
O.OC
1600
0
C
* Air leak in sampling system amounting to 4% of sampled volume.
C2 CO CC2 HC
(PCT ) (PCT ) (PCT) (PPM)
0
380
12000
0
0
0
0
96C
16000
0.77
4.632
6.69
0.75
7.272
5.05
1.20
8.360
4.24
7.00
0.053
6.79
3.90
0.079
8.04
C.85
C .983
8.77
C.74
4.51C
6.79
C.73
7.272
5.15
1.50
8.186
4.04
-------
RUN NUMBER 363*
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE hOT WALL
FUEL AIR
FLOW FLOW
(CFM) (CFM)
PCT AXIAL
STOIC DIST
AIR (IN)
RACIAL MALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.051
0.708
144.3
0.05
O.OC
1600
6
8
0.063
0.708
117.0
0.05
0.0C
16C0
9
14
0.076
0.708
97.8
0.05
O.OC
16C0
25
3C
0.088
0.708
83.5
0.05
O.OC
1600
41
-
0.102
0.708
72.7
0.05
0.00
1600
33
-
0.116
0.708
64.0
0.05
0.00
1600
1
6
0.076
0.708
97.8
1.00
O.OC
1600
36
38
0.088
0.708
83.5
1.00
0.00
1600
40
-
0.102
0.708
72.7
1.00
O.OC
16C0
44
-
0.116
0.708
64.0
1.00
O.OC
16C0
1
-
* Air leak in sampling system amounting to 4Z of sampled volume.
C2
CO
C02
HC
PCT)
(PCT)
(PCT)
(PPM)
7.30
C.028
6.79
C
4.10
C.079
8.04
0
1.30
1.039
8.66
0
C . 86
4.756
6.59
C
C . 69
7.IOC
5.25
560
5.70
6.134
3.25
46000
0.93
0.955
8.66
5
0.76
4.51C
6.59
0
C. 73
7.272
5.05
0
C.96
8.38C
4.14
9500
-------
RUN NUMBER 364
PREMIXEO FLAT FLAME BURNER
PREHEATEC AIR
METHANE HOT WALL
FUEL AIR PCT PREHEAT BURNER AXIAL RACIAL WALL KC NCX C2 CO CC2 HC
FLOW FLOW STOIC TEMP TEMP D1ST OIST TEMP
(CFHJ (CFM) AIR (C) (CI
-------
RUN NUMBER 365
PREMI XfED FLAT FLAME BURNER
STAGEC CCMBUSTI ON
METHANE
HOT WALL
PRIMARY
PRIMARY
SEC.
OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RACIAL
WALL
NC
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOIC
DIST
CIST
TEMP
(CFM)
ICFM)
AIR
(CFM)
AIR
( IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.116
0.561
50.8
0.000
50.8
14.70
0.25
1507
0
0
0.29
11.023
2.66
3900
0.116
0.561
50.8
0.320
79.7
14.70
0.25
1507
0
0
0.29
11.023
2.56
4100
0.116
0.561
50.8
0.320
79.7
34.30
0.25
1507
6
0
C.07
5.412
6.69
530
0.116
0.561
50.8
O.OCO
50.8
34.30
0.25
1507
0
0
C .08
10.779
2.66
2900
0.116
0.561
50.8
0.546
100.1
34.30
0.25
1507
7
8
C.1C
C .440
1C.73
7
0.116
0.561
50.8
0.546
100.1
14.70
0.25
1507
0
0
C.25
11.271
2.56
4400
0.116
0.561
50.8
O.OOC
50.8
14.70
C . 25
1507
0
0
C.25
11.023
2.56
400C
-------
RUN NUMBER 367
PREMIXED FLAT FLAME BURNER
PREHEATED AIR
METHANE HOT WALL
FUEL
AIR
PCT
PREHEAT
BURNER
AXIAL
RADIAL
WALL
NC
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
TEMP
TEMP
01 ST
DIST
TEMP
(CFM)
(CFM)
AIR
CC *
(C)
( INI
(IN)
-------
RUN NUMBER 368
PREMIXED FLAT FLAKE BURNER
PREHEATED AIR
METHANE HOT WALL
FUEL
FLOW
(CFMI
AIR
FLOW
(CFMI
PCT
STCIC
AIR
PREHEAT
TEMP
(C)
BURNER
TEMP
(C)
AXIAL
DIST
< IN)
RACIAL
DIST
(IN)
WALL
TEMP
(C)
NC NOX C2 CO C02 HC
(PPM) (PPM) (PCT) (PCT) (PCT) (PPM)
0.038
0.516
139.6
25.
25.
1C.00
0.25
1584
20
23
5.70
0.000
8.46
C.
0.038
0.516
139.6
25.
25.
3.00
0.25
1584
13
16
5.60
0.000
8.46
0.
0.038
0.516
139.6
25.
25.
1.00
0.25
1584
7
9
5.30
0.000
8.04
0.
0.038
0.516
139.6
25.
25.
0.50
0.25
1584
4
6
5.20
0.000
7.73
0.
0.038
0.516
139.6
25.
25.
0.25
0.25
1584
3
6
5.10
0.000
7.62
0.
0.038
0.516
139.6
25.
25.
0.05
0.25
1584
3
6
5.00
0.028
7.62
2.
u>
\o
-------
RUN NUMBER 369
PREMIXED FLAT FLAKE BURNER
STAGED COMBUSTION
METHANE
HOT WALL
PRIMARY
PRIMARY
SEC.
OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RADIAL
WALL
NC
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOIC
DIST
DIST
TEMP
(CFM)
(CFM)
AIR
(CFM)
AIR
( IN)
( IN)
(C>
(PPM)
(PPM)
(PCT )
(PCT)
(PCT)
(PPM)
0.090
0.516
60.1
O.OCO
60.1
14. 70
C . 25
1507
2
3
C.23
10.304
3.54
16C
0.090
0.516
60.1
0. 342
100.0
14.70
0.25
1507
2
3
C .24
10.304
3.54
150
0.090
0.516
60.1
0.342
100.0
34.30
0.25
1507
8
9
C.18
0.440
10.98
0
0.090
0.516
60.1
O.OCO
60.1
34.30
0.25
1507
2
3
C.ll
9.408
3.74
80
0.090
0.516
60.1
0.515
120.0
34.30
0.25
1507
7
7
3.70
0.232
8.77
0
0.090
0.516
60.1
0.515
120.0
14.70
0.25
1507
2
3
C.25
10.304
3.54
200
0.090
0.516
60.1
O.OOC
60.1
14.70
C.25
1507
2
3
C.25
10.304
3.54
15C
-------
RUN NUMBER 370
PREFIXED FLAT FLAME BURNER
STAGED COMBUST I ON
METHANE
HOT WALL
PRIMARY
PRIMARY
SfcC.
OVERALL
FUEL
AIR
PCT
AIR
PCT
AXIAL
RACIAL
WALL
NC
FLOW
FLOW
STCIC
FLOW
STOIC
DIST
DIST
TEMP
CCFM)
(CFM)
AIR
(CFM )
AIR
( IN)
(IN)
(C)
(PPM)
0.068
0.516
79.2
0.000
79.2
14.70
0.25
1821
40
0.068
0.516
79.2
0.146
101.7
14.70
0.25
1821
38
0.068
0.516
79.2
0. 146
101.7
34.30
0.25
1821
26
0.068
0.516
79.2
0.000
79.2
34.30
0.25
1821
38
0.068
0.516
79.2
0.262
119.6
34.30
C.25
1821
23
0.068
0.516
79.2
0.262
119.6
14.70
0.25
1821
41
0.068
0.516
79.2
0.000
79.2
14.70
0.25
1821
39
NCX
(PPM)
C2
(PCT)
CO
(PCT)
CC2
(PCT)
HC
(PPM)
42
C .32
6.765
6.18
39
C.33
6.931
6.07
28
1.90
1.446
8.77
40
1.10
5.412
5.87
25
3.20
0.181
9.08
43
C.38
6.931
5.97
40
C .39
6.765
6.07
0
0
0
0
0
0
0
-------
RUN NUMBER 371
PREKIXED FLAT FLAKE BURNER
PREHEATED AIR
METHANE HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
BURNER
TEMP
(C)
AXIAL
DIST
( IN)
RACIAL
DIST
(IN)
WALL
TEMP
(C)
NO
(PPK)
0.038
0.516
139.6
170.
1C.00
0.25
1712
23
0.038
0.516
139.6
170.
3.00
0.25
1712
10
0.038
0.516
139.6
170.
1.00
0.25
1712
10
0.038
0.516
139.6
170.
0.50
0.25
1712
4
0.038
0.516
139.6
170.
C.25
0.25
1712
3
0.038
0.516
139.6
170.
C.05
0.25
1712
2
NOX
(PPM)
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPP )
27
6.0C
C.OCC
7.21
13
5.7C
C.CCC
6.90
11
5.10
0.000
5.97
5
4.90
0.000
5.87
4
A.80
0.000
5.56
3
4.70
0.028
5.46
0
c
0
0
0
15
-------
RUN NUMBER 372
PREMIXEC FLAT FLAME BURNER
PREHEATED AIR
METHANE HOT WALL
FUEL AIR PCT
FLOW FLOW STOIC
(CFM) (CFM) AIR
BURNER
TEMP
(C)
AXIAL
DIST
( IN)
RADIAL
DIST
(IN)
WALL
TEMP
(C)
NC
NCX
(PPM) (PPM)
C 2
(PCT)
CO
(PCT)
CC2
(PCT)
HC
(PPM)
0.045
0.516
118.7
170.
1C.00
0.25
1883
170
190
3.50
0.079
8.87
0.
0.045
0.516
118.7
170.
3.00
0.25
1883
37
46
3.40
0.028
8.77
0.
0.045
0.516
118.7
170.
1.00
0.25
1883
22
27
3.00
0.000
7.42
0.
0.045
0.516
118.7
170.
C.50
C.25
1883
17
21
2.90
0.000
7.10
0.
0.045
0.516
118.7
170.
C .25
0.25
1883
13
16
2.80
0.000
6.90
0.
0.045
0.516
118.7
170.
C.05
0.25
1883
10
13
2.70
0.000
6.79
0.
>
•e-
-------
RUN NUMBER 374*
PREMIXED FLAT FLAKE BURNER
FLUE GAS RECYCLE
METHANE HOT WALL
FUEL AIR PCT RECYCLE BURNER AXIAL RADIAL WALL
FLOW FLOW STOIC RATIO TEMP DIST DIST TEMP
(CFM) CCFM) AIR (IN) (IN) (C)
NC NCX C2 CC C02 HC
(PPM) (PPM) (PCT) (PCT) (PCT) (PPM)
0.053
0.516
100.7
0.00
120.
13.10
0.25
1558
60
62
4.70
0.653
7.93
0.
0.053
0.516
ICO.7
0.50
120.
13.10
0.25
1558
6
7
5.60
0.000
7.83
0.
0.053
0.516
100.7
0.50
120.
10.00
0.25
1558
5
6
5.70
0.000
7.73
c.
0.053
0.516
100.7
0.50
120.
3.00
0.25
1558
1
3
7.10
0.309
6.59
1500.
0.053
0.516
100.7
0.50
120.
1.00
0.25
1558
2
3
6.50
0.079
7.10
45CC.
0.053
0.516
100.7
0.50
120.
0.50
0.25
1558
2
3
1C.30
C.000
4.75
27C00.
0.053
0.516
100.7
0.50
120.
C .25
0.25
1558
2
3
11.70
0.000
3.74
4C000.
0.053
0.516
100.7
0.50
120.
C .05
0.25
1558
2
3
12.10
0.000
3.15
45000.
0.053
0.516
100.7
0.50
120.
13.10
0.25
1558
5
6
5.90
0.000
7.62
5.
* Air leak In sampling system amounting to 20% of sampled volume.
-------
RUN NUMBER 375*
PREFIXED FLAT FLAME BURNER
FLUE GAS RECYCLE
METHANE HCT WALL
FUEL AIR PCT RECYCLE BURNER AXIAL RACIAL WALL
FLOW FLOW STCIC RATIO TEMP DIST OIST TEMP
(CFM) (CFM) AIR (C) (IN) (IN) (C)
NC NOX C2 CO CC2 hC
(PPM) (PPM) (PCT) (PCT) (PCT) (PPM)
0.053
0.516
100.7
O.OC
120.
13.10
0.25
1754
83
84
5.80
0.789
7.21
C.
0.053
0.516
100.7
0.25
120.
13.10
0.25
1754
44
48
6.6C
C.053
7.31
c.
0.053
0.516
100.7
0.25
120.
1C.00
0.25
1754
26
29
5.8C
0.104
7.52
0.
0.053
0.516
100.7
0.25
120.
3.00
0.25
1754
17
19
5.3C
C.C28
7.83
C.
0.053
0.516
100.7
0.25
120.
1.00
0.25
1754
12
15
5.6C
C.206
7.31
20.
0.053
0.516
100.7
0.25
120.
C.50
0.25
1754
11
15
5.7C
0.466
7.31
15C.
0.053
0.516
100.7
0.25
120.
C. 25
0.25
1754
5
8
6.6C
C .872
6.48
35CC.
0.053
0.516
100.7
0.25
120.
C.05
0.25
1754
3
4
12.30
C .028
3.25
42CCC.
0.053
0.516
100.7
0.25
120.
13.10
0.25
1754
40
42
5.70
0.104
7.52
5.
Ul
* Air leak in sampling system amounting to 25% of sampled volume.
-------
RUN NUfBER 376*
PREFIXED FLAT FLAME BURNER
FLUE GAS RECYCLE
METHANE HOT WALL
FUEL AIR PCT RECYCLE BURNER AXIAL RADIAL WALL
FLOW FLOW STOIC RATIO TEMP DIST OIST TEMP
(CFH) (CFM) AIR (C) (IN) (IN) (C)
NC NOX C2 CO C02 HC
(PPM) (PPM) (PCT) (PCT) (PCT) (PPM)
0.053
0.516
IOC.7
0.00
120.
13.10
C. 25
1890
165
190
5.70
1.125
7.10
3
0.053
0.516
ICO.7
0.10
120.
13.10
0.25
1890
120
125
5.5C
1.211
7.CO
C
0.053
0.516
100.7
0.10
120.
1C.C0
C. 25
1890
58
60
5.90
0.955
7.10
0
0.053
0.516
100.7
0.10
120.
3.00
G. 25
1890
46
47
5.30
0.653
7.42
0
0.053
0.516
100.7
0.10
120.
1.00
C. 25
1890
29
3C
5.20
0.546
6.59
0
0.053
0.516
LOO.7
0.10
120.
C.5C
C.25
1890
37
38
5.70
0.872
7.52
0
0.053
0.516
IOC.7
0.10
120.
C. 25
C.25
1890
28
31
5.80
1.153
7.62
35
0.053
0.516
ICO.7
0.10
120.
C. 05
0.25
1890
2
3
12.00
0.899
3.54
40000
0.053
0.516
ICO.7
0.10
120.
13. 10
0.25
1890
46
48
5.60
1.039
7.00
20
T
•e-
-------
RUN NUMBER 377*
PREMIXED FLAT FLAME BURNER
PREHEATED AIR
METHANE HOT WALL
FUEL
AIR
PCT
BURNER
AXIAL
RACIAL
MALL
KC
NCX
C2
CO
CC2
HC
FLOW
FLOW
STOIC
TEMP
DIST
DIST
TEMP
(CFM)
(CFM)
AIR
(C)
( IN)
(IN)
(C)
(PPM)
(PPM)
CPCT)
(PCT)
(PCT)
(ppr)
0.053
0.516
100.7
80.
10.00
0.25
1951
ICO
105
5.30
1.039
7.10
5
0.053
0.516
100.7
60.
3.00
0.25
1951
44
46
5.10
0.599
7.21
1
0.053
0.516
100.7
45.
1.00
0.25
1951
34
35
4.90
0.546
6.28
0
0.053
0.516
100.7
45.
0.50
C.25
1951
45
46
5.80
0.872
7.21
0
0.053
0.516
100.7
40.
C. 25
0.25
1951
38
41
5.70
1.125
7.62
0
0.053
0.516
100.7
40.
C. 05
0.25
1951
3
4
14.00
0.053
2.C8
55000
* Air leak In sampling system amounting to 252 of sampled volume.
>
i
•t-
>4
-------
RUN NUMBER 378
PREMIXED FLAT FLAKE BURNER
WATER VAPCR ADD ITICN
METHANE HOT WALL
DRY
FUEL
AIR
PCT
ABS
BURNER
AXIAL
RACIAL
WALL
NO
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
HUMID
TEMP
DIST
DIST
TEMP
AIR
(PCT)
(C)
( IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.045
0.516
118.7
0.0
120.
13. 10
0.25
1800
170
190
3.00
C.000
8.98
0
0.045
0.516
118.7
2.0
120.
1C.00
0.25
1800
37
53
2.80
0.026
8.87
0
0.045
0.516
118.7
2.0
120.
3.00
0.25
1800
14
23
2.70
0.000
8.87
C
0.045
0.516
118.7
2.0
120.
1.00
0.25
1800
16
24
2.1C
0.028
7.52
0
0.045
0.516
118.7
2.0
120.
C. 50
0.25
1800
14
23
3.0C
0.104
10.73
C
0.045
0.516
118.7
2.0
120.
C. 25
0.25
1800
10
17
3.7C
C.104
9.60
c
0.045
0.516
118.7
2.0
120.
C. 05
0.25
1800
1
3
18.OC
C.000
0.29
750CC
0.045
0.516
118.7
O.C
120.
13.10
0.25
1800
170
195
3.00
0.028
8.87
5
-------
RUN NUMBER 379
ADIABATIC STIRRED COMBUSTOR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR
FLOW FLOW
(CFM) CCFM)
PCT AXIAL
STOIC OIST
AIR (IN)
RADIAL MALL
DIST TEMP
(IN) (C)
NO NOX
(PPM) (PPM)
0.041
0.516
131.9
10.10
O.OC
1725
100
115
0.041
0.516
131.9
3.00
O.OC
1725
27
34
0.041
0.516
131.9
1.00
O.OC
1725
11
17
0.041
0.516
131.9
0.50
O.OC
1725
12
18
0.041
0.516
131.9
0.25
O.OC
1725
7
17
0.041
0.516
131.9
0.05
0.00
1725
5
11
0.041
0.516
131.9
10.10
0.00
1725
90
105
C2 CO C02 HC
(PCT) (PCT) (PCT) (PPM)
4.50
0 .079
8.98
0
4.40
0.1C4
9.C8
1
4.50
0.181
8.87
0
4.40
0.155
8.77
1
4.50
0.309
8.56
350
5.10
0.493
8.25
1200
4.50
0.079
9.08
2
-------
RUN NUMBER 380
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
METHANE
HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM>
PCT
STOIC
AIR
AXIAL
DIST
(IN)
RAOIAL
OIST
(IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
(PPM)
0.064
0.516
83.8
10.10
o.oc
1824
75
77
0.064
0.516
83.8
3.CO
o.oc
1824
62
63
0.064
0.516
83.8
1.00
0.00
1824
44
47
0.064
0.516
83.8
0.50
0.00
1824
26
30
0.064
0.516
83.8
0.25
0.00
1824
25
39
0.064
0.516
83.8
0.05
o.oc
1824
13
32
0.064
0.516
83.8
10.10
0.00
1824
67
69
02
CO
C02
HC
PCT)
(PCT)
(PCT)
(PPM)
C. 18
6.287
6.90
0
C . 19
5.984
7.10
0
0.18
5.693
7.42
90
0.53
5.551
7.21
3000
C.75
5.412
7.00
4200
2.00
5.551
6.48
9500
C . 19
6.287
7.00
7
-------
RUN NUMBER 381
ADIABATIC STIRREO COMBUSTGR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL AIR PCT AXIAL RADIAL WALL NO NOX
FLOW FLOW STOIC DIST OIST TEMP
(CFM) (CFM) AIR (IN) (IN) (C) (PPM) (PPM)
0.051
0.516
105.3
10.10
0.00
1953
650
860
0.051
0.516
105.3
3.00
0.00
1953
105
115
0.051
0.516
105.3
1.00
0.00
1953
36
45
0.051
0.516
105.3
0.50
O.OC
1953
28
37
0.051
0.516
105.3
0.25
O.OC
1953
28
35
0.051
0.516
105.3
0.05
O.OC
1953
16
28
0.051
0.516
105.3
10.10
O.OC
1953
760
780
C2 CO CC2 HC
(PCT) (PCT) (PCT) (PPM)
0.58
1.096
10.73
3
0.58
1.211
10.98
0
0.72
1.182
10.73
1
0.73
1.153
10.73
35
1.00
1.096
10.49
1000
2.60
1.973
8.66
6500
C.54
1.182
10.98
5
-------
RUN NUMBER 382
ADIABATIC STIRREO CGMBUSTCR
NORMAL CCMBUSTION
METHANE HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
DIST
( IN)
RAOIAL
DIST
(IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
(PPM)
0.025
0.248
101.3
10.10
0.00
1953
1300
135C
0.025
0.248
101.3
3.00
0.00
1953
100
110
0.025
0.248
101.3
1.00
O.OC
1953
45
51
0.025
0.248
101.3
0.50
0.00
1953
36
42
0.025
0.248
101.3
0.25
0.00
1953
37
42
0.025
0.248
101.3
0.05
O.OC
1953
35
41
0.025
0.248
101.3
10.10
O.OC
1953
1250
130C
C2
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
0.60
0.983
10.98
0.58
0.519
11.48
C.67
0.599
11.48
0.70
0.573
11.23
0.65
0.519
11.48
1.20
1.153
10.73
0.66
0.872
10.98
1
0
0
1
0
7
2
-------
RUN NUMBER 383
AOIABATIC STIRRED COMBUSTGR
NORMAL COMBUSTION
METHANE HOT WALL
FUEL
AIR
PCT
AXIAL
RACIAL
WALL
NO
NOX
FLOW
FLOW
STOIC
OIST
OIST
TEMP
(CFM)
(CFM)
AIR
(IN)
( IN)
(C)
(PPM)
(PPM)
0.051
0.492
100.3
10.10
O.OC
1953
760
78C
0.051
0.492
ICO.3
0.25
o.cc
1953
39
48
0.045
0.492
113.0
0.25
O.OC
1953
21
3C
0.040
0.492
129.1
0.25
0.00
1953
14
21
0.057
0.492
89.9
0.25
0.00
1953
55
58
0.063
0.492
81.3
0.25
O.OC
1953
54
57
0.069
0.492
74.1
0.25
O.OC
1953
42
51
0.055
0.492
93.8
0.25
0.00
1953
49
52
02
CO
CC2
HC
PCT)
(PCT)
(PCT)
(PPM)
C . 56
1.153
10.98
3
0.97
1.328
10.73
0
2.90
0.466
9.92
C
5.20
0.258
8.87
1
C.27
3.506
9.29
5
0.19
5.551
7.73
80
0.25
7.272
6.59
1700
0.39
2.632
9.71
5
-------
RUN NUMBER 384
ADIABATIC STIRRED COMBUSTCR
PREHEATED AIR
METHANE HOT WALL
FUEL
AIR
PCT
BURNER
AXIAL
RADIAL
WALL
NO
FLOW
FLOW
STOIC
TEMP
OIST
DIST
TEMP
(CFMI
tCFM)
AIR
(CI
(IN)
(IN)
(C)
(PPM)
0.021
0.248
121.1
150.
1C.10
0.00
1800
440
0.021
0.248
121.1
150.
3.00
0.00
1800
44
0.021
0.248
121.1
150.
1. 00
0.0 0
1800
26
0.021
0.248
121.1
150.
0.50
0.00
1800
21
0.021
0.248
121.1
150.
0.25
0.00
1800
20
0.021
0.248
121.1
150.
0.05
0.00
1800
15
NOX C 2 CO C02 HC
(PPM) (PCT) (PCTI (PCT) (PPM)
0
0
0
0
1
1
490
4.50
0.129
9.29
58
4.60
0.053
9.39
36
4.6C
0.079
9.39
29
4.60
0.079
9.29
27
4.70
0.129
9.29
24
4.80
0.414
9.08
-------
RUN NUMBER 385
ADIABATIC STIRRED COMBUSTCR
PREHEATED AIR
METHANE HOT WALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
BURNER
TEMP
(C)
AXIAL
DIST
(IN)
RACIAL
DIST
(IN)
WALL
TEMP
(C>
NO NOX C2 CO C02 HC
(PPM) (PPM) (PCT) (PCT) (PCT) (PPM)
0.041
0.492
125.6
150.
10.10
0.00
1800
220
245
4.4C
0.129
9.29
1.
0.041
0.492
125.6
150.
3.00
0.00
1800
40
52
4.30
C.079
9.50
C.
0.041
0.492
125.6
150.
1.00
0.00
1800
21
29
4.4C
0.155
9.50
0.
0.041
0.492
125.6
150.
C. 50
0.00
1800
16
24
4.40
C .206
9.39
0.
0.041
0.492
125.6
150.
0.25
0.00
1800
12
21
4.50
0.283
9.29
1.
0.041
0.492
125.6
150.
0.05
0.00
1800
10
18
4.80
0.762
8.77
1.
T
1/1
Ut
-------
RUN NUMBER 386
AOIABATIC STIRREO COMBUSTCR
NORMAL COMBUSTION
HYDROGEN HOT HALL
FUEL
AIR
PCT
AXIAL
RACIAL
WALL
NO
NOX
C2
CO
C02
HC
FLOW
FLOW
STOIC
DIST
DIST
TEMP
(CFM)
(CFM)
AIR
(IN)
( IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
0.346
0.492
59.7
10.10
0.00
1910
16
1
0.24
o.ooc
0.00
0
0.346
0.492
59.7
3.00
0.00
1910
6
1
0.23
o.ooc
0.00
0
0.346
0.492
59.7
1.00
o.oc
1910
5
1
0.23
o.ooc
0.00
0
0.346
0.492
59.7
0.50
0.00
1910
5
1
C. 22
o.occ
0.00
0
0.346
0.492
59.7
0.25
0.00
1910
4
1
0.22
o.ooc
0.00
0
0.346
0.492
59.7
0.05
0.00
1910
4
1
0.45
0.000
0.00
0
!>•
U»
-------
RUN NUMBER 387
AOIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
HYDROGEN HCT MALL
FUEL
FLOW
(CFM)
AIR
FLOW
(CFM)
PCT
STOIC
AIR
AXIAL
DIST
(IN)
RAOIAL
DIST
(IN)
WALL
TEMP
(C)
NO
(PPM)
NOX
(PPM)
0.172
0.492
130.0
10.10
O.OC
1897
620
680
0.172
0.492
130.0
3.00
0.00
1897
34
44
0.172
0.492
130.0
1.00
0.00
1897
13
18
0.172
0.492
130.0
0.50
O.OC
1897
10
14
0.172
0.492
130.0
0.25
O.OC
1897
8
11
0.172
0.492
130.0
0.05
O.OC
1897
7
10
02
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM)
4.70
O.OOC
o.co
4.80
O.OOC
0.00
4.70
O.OOC
0.00
4.60
O.OCC
0.00
4.70
O.OOC
0.00
5.00
c.occ
0.00
0
0
0
0
0
0
-------
RUN NUMBER 388
AD IABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
HYOROGEN HOT MALL
FUEL
AIR
PCT
AXIAL
RACIAL
WALL
NO
NOX
FLOW
FLOW
STCIC
OIST
GIST
TEMP
(CFM1
(CFMI
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
0.089
0.248
127.0
10.10
0.00
1897
1150
125C
0.089
0.248
127.0
3.CO
0.00
1897
36
51
0.089
0.248
127.0
1.00
O.OC
1897
13
20
0.089
0.248
127.0
0.50
0.00
1897
9
14
0.089
0.248
127.0
0.25
0.00
1897
8
12
0.089
0.248
127.0
0.05
0.00
1897
8
11
02
(PCT)
CO
(PCT)
C02
(PCT)
HC
(PPM J
4.30
O.OOC
0.00
4.80
O.OOC
o.co
4.70
0.000
0.00
4.50
0.000
0.00
4.50
0.000
0.00
5.30
0.000
0.00
0
0
0
0
0
0
-------
RUN NUMBER 389
ADIABATIC STIRRED COMBUSTCR
NORMAL COMBUSTION
HYDROGEN HOT WALL
FUEL
AIR
PCT
AXIAL
RADIAL
WALL
NO
NOX
FLOW
FLOW
STOIC
DIST
DIST
TEMP
(CFM)
(CFM I
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
0.159
0.492
150.7
10.10
0.00
1685
33
45
0.159
0.492
150.7
3.00
0.00
1685
11
17
0.159
0.492
150.7
1.00
0.00
1685
7
10
0.159
0.492
150.7
0.50
G.OC
1685
6
9
0.159
0.492
150.7
0.25
0.00
1685
5
8
0.159
0.492
150.7
0.05
G.OC
1685
5
7
C2
(PCT1
CO
(PCT)
C02
(PCT)
HC
(PPM J
7.20
0.000
0.00
7.20
0.000
0.00
7.00
0.000
0.00
6.90
O.OOC
0.00
6.80
0.000
0.00
7.10
0.000
0.00
0
0
0
0
0
0
-------
RUN NUMBER 390
AOIABATIC STIRRED COMBUSTCR
H2 ADDITION
CARBON MONOXIDE HOT WALL
FUEL
AIR
PCT
ADDITIVE
OVERALL
AXIAL
RADIAL
WALL
NO
NOX
02
CO
C02
HC
FLOW
FLOW
STOIC
FLOW
STOICH
DIST
DIST
TEMP
(CFMI
(CFMI
AIR
(H2)
AIR
(IN)
(IN)
(C>
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
(CO)
0.133
0.516
163.0
0.023
139.0
10.10
0.00
1736
9C0
950
6.80
0.335
0.
0.133
0.516
163.0
0.023
139.0
3.00
0.00
1736
135
160
6.50
0.232
*****
0.
0.133
0.516
163.0
0.023
139.0
1.00
0.00
1736
38
45
6.20
0.079
*****
0.
0.133
0.516
163.0
0.023
139.0
0.50
0.00
1736
20
27
6.30
0.388
*****
0.
0.133
0.516
163.0
0.023
139.0
0.25
0.00
1736
12
19
6.50
0.816
*****
0.
0.133
0.516
163.0
0.023
139.0
0.05
0.00
1736
10
17
6.70
1.417
24.72
1.
:>
ON
o
-------
RUN NUMBER 391
AOIABATIC STIRRED COMBUSTCR
H2 ADDITION
CARBON MONOXIDE HOT HALL
FUEL
AIR
PCT
ADDITIVE
OVERALL
AXIAL
RADIAL
HALL
NO
NOX
02
CO
CO 2
HC
FLOW
FLOW
STOIC
FLOW
STOICH
OIST
DIST
TEMP
(CFM)
(CFH)
AIR
(H2)
AIR
< IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
(CO)
0.151
0.516
143.6
0.023
124.6
10.10
0.00
1877
880
930
5.10
0.493
*****
0.
0.151
0.516
143.6
0.023
124.6
3.00
0.00
1677
155
175
5.20
0.546
*****
0.
0.151
0.516
143.6
0.023
124.6
1.00
0.00
1877
3B
50
5.00
0.388
*****
0.
0.151
0.516
143.6
0.023
124.6
0.50
0.00
1877
23
33
5.20
0.707
*****
0.
0.151
0.516
143.6
0.023
124.6
0.25
0.00
1877
16
25
5.40
1.211
*****
0.
0.151
0.516
143.6
0.023
124.6
0.05
0.00
1877
13
21
5.60
1.845
*****
0.
-------
RUN NUMBER 392
ADIABATIC STIRRED COMBUSTGR
H2 ADDITION
CARBON MONOXIDE HOT WALL
FUEL
AIR
PCT
ADDITIVE
OVERALL
AXIAL
RADIAL
WALL
NO
NOX
02
CO
CG2
HC
FLOW
FLOW
STOIC
FLOW
STOICH
DIST
CIST
TEMP
(CFM)
(CFH)
AIR
(CFM)
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
(CO)
(H2)
0.429
0.516
50.6
0.023
48.0
10.10
0.00
1877
44
46
0.11
******
*****
0.
0.429
0.516
50.6
0.023
48.0
3.00
0.00
1877
30
31
0.11
******
*****
0.
0.429
0.516
50.6
0.023
48.0
1.00
0.00
1877
17
19
0.10
******
*****
0.
0.429
0.516
50.6
0.023
48.0
0.50
0.00
1877
12
14
0.10
******
*****
0.
0.429
0.516
50.6
0.023
48.0
0.25
0.00
1877
14
15
0.12
******
*****
0.
0.429
0.516
50.6
0.023
48.0
0.05
0.00
1877
12
14
0.14
******
*****
0.
o>
ls>
-------
RUN NUMBER 393
ADIABATIC STIRRED COMBUSTCR
H2 ADDITION
CARBON MONOXICE HOT WALL
FUEL
AIR
PCT
ADDITIVE
OVERALL
AXIAL
RADIAL
WALL
NO
NOX
02
CO
CQ2
HC
FLOW
FLOW
STOIC
FLOW
STOICH
DIST
CIST
TEMP
(CFHI
C CFH)
AIR
(CFM)
AIR
(IN)
(IN)
(C)
(PPM)
(PPM)
(PCT)
(PCT)
(PCT)
(PPM)
(CO)
(H2)
0.429
0.516
50.6
0.000
50.6
10.10
0.00
1877
240
245
0.19
******
*****
0.
0.429
0.516
50.6
O.OCO
50.6
3.00
0.00
1677
155
160
0.19
******
*****
0.
0.429
0.516
50.6
0.000
50.6
1.00
0.00
1877
42
43
0.19
******
*****
0.
0.429
0.516
50.6
0.000
50.6
0.50
0.00
1877
27
27
0.19
******
*****
0.
0.429
0.516
50.6
O.OCO
50.6
0.25
0.00
1877
16
17
0.19
******
*****
0.
0.429
0.516
50.6
0.000
50.6
0.05
0.00
1877
8
11
3.50
******
*****
0.
:>
o\
w
-------
B-l
APPENDIX B
EVALUATION OF PROBABLE RELATIVE IMPORTANCE OF
REACTION STEPS FOR METHANE/AIR COMBUSTION
This section contains a reaction-by-reaction evaluation of the
potential importance of each of the 322 reactions considered in this
study. It is extremely important to understand the groundrules for tho
evaluation and scope of its applicability. The comments found in this
section refer only to the combustion of methane-air from 80-125% stoichio-
metric air, from 1500-2500K. This has been stated elsewhere in this
report, but bears repeating. The use of the information in this section
outside the limits mentioned, may be valid, but should be approached with
caution-. Not only would the relative importance of the given reactions
require evaluation for specific conditions but other species and, there-
fore, additional reactions might have to be considered outside those
limits. And of course, other reaction systems such as higher hydrocarbons
of fuel-nitrogen containing systems would bear their own evaluations.
The headings in this section are as follows:
Headings
REACTION
HR
NOTES
Description
Written in both directions
Reaction number indicated
F ¦ Forward
R « Reverse
AIL. for both directions given at 2000K
(mid-range of 150Q-2500K)
note: in the thermochemical tables
AHr298 l-s used in the expression
for log Kj,
A
B
C
*
Probably important
Possibly important
Probably unimportant
Flag indicating reaction was raced
either A or B
COMMENTS
Notes explaining reasons for ranking
-------
REACTION
HR NOTES
IF. CH ~ CHN » CH2 + CN 20.3 B *
1R. CH2 ~ CN = CH ~ CHN -20.3 B *
2F. CH ~ CHO = CH2 + CO -85.5 C
2R. CH2 ~ CO * CH ~ CHO 85.5 C
3F. CH + CH20 « CHO ~ CH2 -15.6 C
3R. CHO ~ CH2 = CH + CH20 15.6 C
4F. CH ~ CH20 = CH3 «• CO -108.6 C
4R. CH3 ~ CO » CH + CH20 108.6 C
5F. CH ~ CH3 ® CH2 ~ CH2 7.4 C
5R. CH2 ~ CH2 - CH * CH3 -7.4 C
6F. CH ~ CH30 « CHO + CH3 -102.7 C
6R. CHO ~ CH3 = CH + CH30 102.7 C
7F. CH + CH30 « CH2 + CH20 -79.6 C
7R. CH2 ~ CH20 a CH + CH30 79.6 C
8F. CH + CH30 « CH4 + CO -191.3 C
SR. CH4 ~ CO = CH + CH30 191.3 C
9F. CH + CH4 » CH2 ~ CH3 3.0 B *
9R. CH2 ~ CH3 * CH + CH4 -3.0 B *
10F. CH + C02 * CHO ~ CO -68.3 B *
10R. CHO ~ CO » CH + C02 68.3 C
COMMENTS
CONSIDER BOTH DIRECTIONS, FUEL RICH
POSSIBLE ROLE CN/HCN
PROBABLY MINOR
FORWARD UNIMPORTANT FOR CHO REMOVAL
H, Or HO MORE LIKELY REACTION PARTNERS
REVERSE ENDOTHERMIC
CH, CH2 MINOR RX PARTNERS FOR CHO, CH20
CH MINOR RX PARTNER FOR CH20
REVERSE HIGHLY ENDOTHERMIC
(CH) (CH3) AND (CH2HCH2) LIKELY SMALL
POSSIBLE FUEL RICH
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS, FUEL RICH
CH4 STARTING MATL, CH3 INITIAL INTERMED
THERMALLY NEUTRAL
CONSIDER FORWARD, FUEL RICH
(C02) HIGH, PATH FROM CH TO CO
REVERSE ENDOTHERMIC
-------
REACTION
HR NOTES
11F. CH ~ H + H = CH2 + M -105.1 C
11R. CH2 ~Ms CH + H + M 105.1 C
12F. CH + HN » CHN + H -145.4 C
12R. CHN ~ H » CH 4 HN 145.4 C
13F. CH ~ HN » CH2 ~ N -26.2 C
13R. CH2 + N » CH ~ HN 26.2 C
14F. CH «• HN « CN ~ H2 -128.4 C
14R. CN ~ H2 • CH + HN 128.4 C
15F. CH ~ HNO * CHN «¦ HO -123.8 C
15R. CHN + HO « CH ~ HNO 123.8 C
16F. CH «• HNO « CHO ~ HN -67.8 C
16R. CHO ~ HN a CH + HNO 67.8 C
17F. CH ~ HNO » CH2 ~ NO -52.4 C
17R. CH2 ~ NO » CH t HNO 52.4 C
18F. CH ~ HNO * CH20 + N -78.4 C
18ft. CH20 + N = CH + HNO 78.4 C
19F• CH + HNO « CN + H20 -121.7 C
19R. CN ~ H20 ' CH ~ HNO 121.7 C
20F. CH ~ HO * CHO ~ H -89.4 B »
20R. CHO + H » CH ~ HO 89.4 C
COMMENTS
THIRO ORDERt LOW CONC IN FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
HIGHLY ENDOTHERMIC REVERSE
LOW CONCENTRATIONS BOTH DIRECTIONS
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION
FORWARD POSSIBLE FOR NOH STRUCTURE
CONCENTRATIONS LOW
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS BOTH DIRECTIONS
REVERSE ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
CH2 + NO = CH20 + N MORE LIKELY REVERSE
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION FOR NOH STRUCTURE
CONSIDER FORWARD
REVERSE ENDOTHERMIC
-------
REACTION HR NOTES
21F. CH + HO - CH2 +0 1.2 C
21R. CH2 ~ 0 = CH + HO -1.2 C
22F. CH ~ HO + M » CH20 + M -178.9 C
22R. CH20 * M * CH ~ HO ~ M 178.9 C
23F. CH + HO « CO + H2 -178.3 C
23R. CO ~ H2 = CH * HO 178.3 C
24F. CH ~ H02 » CHO + HO -129.6 C
24R. CHO * HO = CH ~ H02 129.6 C
25F- CH ~ H02 = CH2+ 02 -54.7 B *
25R. CH2+ 02 a CH + H02 54.7 C
26F. CH + H02 * CH20 + 0 -112.8 C
26R. CH20 + 0 « CH + H02 112.8 C
27F. CH + H02 » CO ~ H20 -233.4 C
27R. CO ~ H20 » CH + H02 233.4 C
28F. CH ~ H02 « C02 «¦ H2 -239.7 C
28R. C02 ~ H2 = CH + H02 239.7 C
29F. CH * H2 * CH2 + H 3.4 B *
29R. CH2 ~ H = CH ~ H2 -3.4 B *
30F. CH ~ H2 ~ M * CH3 ~ M -109.2
30R. CH3 + M » CH ~ H2 + M 109.2
C
C
COMMENTS
CH ~ HO = CHO ~ H MORE LIKELY FORWARD
CH2 + 0 = CHO + H MORE LIKELY REVERSE
THIRD ORDER, LOW CONCENTRATION FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
CH + HO = CHO + H MORE LIKELY FORWARD
REVERSE HIGHLY ENDOTHERMIC
H-02 WEAKER THAN HO-O
CH + H02 = CH2 + H02 MORE LIKELY FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
CH ~ H02 = CH2 ~ 02 MORE LIKELY FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS FUEL RICH
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION HR NOTES
31F. CH ~ H20 » CHO + H2 -74.5 C
31R. CHO * H2 = CH + H20 74.5 C
32F. CH ~ H20 « CH2+ HO 18.2 B *
32R. CH2+ HO = CH ~ H20 -18.2 B ~
33F. CH ~ H20 * CH20 + H -55.6 C
33R. CH20 + H * CH + H20 55.6 C
34F. CH ~ H20 = CH3 + 0 12.0 C
34R. CH3 ~ 0 3 CH + H20 -12.0 C
35F. CH *- H20 ~ M = CH30 + M -81.1 C
35R. CH30 + H = CH ~ H20 + M 81.1 C
36F. CH ~ N + M = CHN + M -224.3 C
36R. CHN •»'M«CH + N+ M 224.3 C
37F. CH ~ N = CN ~ H -98.9 C
37R. CN ~ H = CH + N 98.9 C
38F. CH ~ NO * CHN + 0 -70.2 B *
38R. CHN + 0 = CH ~ NO 70.2 C
39F. CH ~ NO « CHO ~ N -41.6 B ~
39R. CHO ~ N » CH ~ NO 41.6 C
40F. CH ~ NO ¦ CN ~ HO
40R. CN ~ HO = CH + NO
-51.1
51.1
C
C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS FUEL RICH
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
THIRD ORDER, LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD FUEL RICH
REVERSE ENDOTHERMIC
CONSIDER FORWARD FUEL RICH
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION
-------
REACTION
HR NOTES
41F. CH ~ NO » CO ~ HN
41R. CO ~ HN ¦ CH ~ NO
¦101.0
101.0
C
C
42F. CH «• N02 « CHN ~ 02
42R. CHN ~ 02 * CH ~ N02
•117.5
117.5
C
C
43F. CH + N02
43R. CHO ~ NO
CHO NO
CH ~ N02
¦121.0
121.0
C
C
44F. CH ~ N02
44R. CN ~ H02
CN + H02
CH + N02
-42.4
42.4
C
C
45F. CH + N02
45R. CO + HNO
CO ~ HNO
CH + N02
¦154.1
154.1
C
C
46F. CH ~ N02 » C02 ~ HN
46R. C02 ~ HN » CH ~ N02
¦153.7
153.7
C
C
47F. CH + N2 * CHN ~ N
47R. CHN + N * CH + N2
5.1
-5.1
A *
B *
48F. CH + N2 » CN ~ HN
48R. CN ~ HN 8 CH + N2
51.6
-51.6
B *
B ~
49F. CH + N20
49R. CHN ~ NO
CHN ~ NO
CH ~ N20
109.1
109.1
C
C
50F. CH + N20
50R. CHO + N2
CHO ~ N2
CH + N20
¦155.8
155.8
C
C
COMMENTS
FOUR-CENTER REACTION
NOT LIKELY TO .BE ELEMENTARY REACTION
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
FORWARD IS LOW ENERGY N-N BREAKING
POTENTIALY VERY IMPORTANT
SPIN RETARDED
CONSIDER BOTH DIRECTIONS
FOUR-CENTER REACTION
FORWARD IS MODERATE ENERGY N-N BREAKING
CONSIDER BOTH DIRECTIONS FOR SCREENING
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
-------
REACTION
HR NOTES
51F. CH ~ N20 = CN + HNO -36.4 C
51R. CN ~ HNO * CH ~ N20 36.4 C
52F. CH 0 ~ M = CHO + M -195.7 C
52R. CHO ~ M = CH 0 ~ M 195.7 C
53F. CH ~ 0 = CO ~ H -176.2 B *
53R. CO + H « CH ~ 0 176.2 C
54F. CH ~ 02 = CHO * 0 -73.7 B *
54R. CHO + 0 = CH ~ 02 73.7 C
55F. CH ~ 02 = CO ~ HO -160.4 C
55R. CO ~ HO = CH + 02 160.4 C
56F. CH «• 02 = C02 + H -181.6 C
56R. C02 ~ H » CH ~ 02 181.6 C
57F. CHN ~HsCN+HtM 125.4 C
57R. CN H + M = CHN + M -125.4 C
58F. CHN ~ CHO « CH20 + CN 35.9 C
58R. CH20 + CN a CHN ~ CHO -35.9 C
59F. CHN ~ CH2 * CH3 ~ CN 12.9 B ~
59R. CH3 ~ CN » CHN ~ CH2 -12.9 B *
60F. CHN ~ CH20 - CH30 ~ CN 99.9 C
60R. CH30 ~ CN = CHN + CH20 -99.9 C
COMMENTS
LOW CONCENTRATIONS BOTH DIRECTIONS
THIRD ORDER* LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION
CH + 02 = CHO + 0 MORE LIKELY FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
FORWARD HIGHLY ENDOTHERMIC
THIRD ORDER* LOW CONCENTRATIONS REVERSE
LOW CONCENTRATIONSt STERIC HINDRANCE
CONSIDER FUEL RICH
REVERSE POSSIBLE DURING EARLY STAGES
STERIC HINDRANCE, LOW CONCENTRATIONS
BOTH DIRECTIONS
-------
REACTION
HR NOTES
61F. CHN ~ CH3 * CH4 ~ CN 17.3 B *
61R. CH4 ~ CN = CHN ~ CH3 -17.3 B ~
62F. CHN ~ CO - CHO + CN
62R. CHO ~ CN « CHN + CO
105.9
•105.9
C
C
63F. CHN ~ H » CH2 ~ N
63R. CH2 ~ N » CHN ~ H
119.2
¦119.2
C
C
64F. CHN ~ H = CN ~ H2
64R. CN ~ H2 = CHN ~ H
17.0
-17.0
B
B
~
*
65F. CHN + HN * CH2 ~ N2 -31.3 C
65R. CH2 ~ N2 * CHN ~ HN 31.3 B *
66F. CHN + HNO » CH2 ~ N20 56.8 C
66R. CH2 ~ N20 » CHN ~ HNO -56.8 C
67F. CHN ~ HNO = CH20 ~ N2 -83.5 C
67R. CH20 + N2 = CHN + HNO 83.5 C
68F. CHN + HO « CHO + HN 56.0 C
68R. CHO + HN * CHN + HO -56.0 C
69F. CHN ~ HO = CH2 + NO 71.4 C
69R. CH2 + NO = CHN + HO -71.4 C
70F. CHN «• HO = CH20 + N 45.4 C
70R. CH20 + N » CHN + HO -45.4 C
COMMENTS
CONSIDER BOTH DIRECTIONS FUEL RICH
REVERSE POSSIBLE DURING EARLY STAGES
FORWARD HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
FORWARD HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
CONSIDER BOTH DIRECTIONS FUEL RICH
LOW CONCENTRATIONS FORWARD
CONSIDER REVERSE FOR-N-N BREAKING
FOUR-CENTER REACTION
LOW CONCENTRATIONS BOTH DIRECTIONS
FOUR-CENTER REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
CH2 ~ NO = CH20 + N MORE LIKELY REVERSE
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION HR NOTES
71F. CHN ~ HO » CN + H20 2.1 8 *
71R. CN ~ H20 » CHN + HO -2.1 B *
72F. CHN * H02 » CHO ~ HNO -5.8 C
72R. CHO ~ HNO » CHN + H02 5.8 C
73F. CHN ~ H02 » CH2 ~ N02 62.8 C
73R. CH2 ~ N02 ¦ CHN ~ H02 -62.8 C
74F. CHN ~ H02 » CH20 ~ NO -42.6 C
74R. CH20 ~ NO = CHN ~ H02 42.6 C
75F. CHN ~ H2 ¦ CH2 ~ HN 148.8 C
75R. CH2 ~ HN = CHN ~ H2 -148.8 C
76F. CHN ~ H2 « CH3 ~ HN 115.1 C
76R. CH3 ~ HN » CHN + H2 -115.1 C
77F. CHN ~ H20 = CH2 ~ HNO 142.0 C
77R. CH2 ~ HNO = CHN ~ H20 -142.0 C
78F. CHN ~ H20 » CH20 + HN 89.8 C
78R. CH20 ~ HN * CHN + H20 -89.8 C
79F. CHN ~ H20 * CH3 + NO 82.2 C
79R. CH3 * NO s CHN + H20 -82.2 C
80F. CHN ~ H20 ® CH30 + N 143.3 C
80R. CH30 ~ N = CHN ~ H20 -143.3 C
COMMENTS
CONSIDER BOTH DIRECTIONS FUEL RICH
UNLIKELY TO 8E ELEMENTARY REACTION
FOUR-CENTER REACTION
STERIC HINDRANCE
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
C-N BOND STRONG
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
STERIC HINDRANCE
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION! HR NOTES
81F. CHN + N * CN + HN 46.5 C
81R. CN ~ HN = CHN + N -46.5 C
82F. CHN ~ NO = CHO + N2 -46.7 C
82R. CHO ~ N2 = CHN + NO 46.7 C
83F. CHN ~ NO * CN + HNO 72.7 C
83R. CN + HNO s CHN + NO -72.7 C
84F. CHN ~ N02 = CHO + N20 -11.8 C
84R. CHO + N20 * CHN + N02 11.8 C
8-5F. CHN + 0 = CHO * N 28.6 B *
85R. CHO ~ N = CHN + 0 -28.6 B *
86F. CHN ~ 0 » CN + HO 19.1 B *
86R. CN ~ HO = CHN «• 0 -19.1 B *
87F. CHN ~ 0 * CO ~ HN -30.8 C
87R. CO ~ HN = CHN + 0 30.8 C
88F. CHN ~ 02 « CHO + NO -3.4 C
88R. CHO ~ NO = CHN ~ 02 3.4 C
89F. CHN + 02 = CN ~ H02 75.1 C
89R. CN + H02 = CHN + 02 -75.1 C
90F. CHN ~ 02 = CO + HNO -36.6 C
90R. CO ~ HNO ¦ CHN + 02 36.6 C
COMMENTS
LOW CONCENTRATIONS BOTH DIRECTIONS
FOUR-CENTER REACTION
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
FOUR-CENTER REACTION
STERIC HINDRANCE
CONSIDER BOTH DIRECTIONS FUEL RICH
CONSIDER BOTH DIRECTIONS FUEL RICH
NOTE- CNO POSSIBLE PRODUCT REVERSE
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
CHN AND 02 NOT LIKELY HI SIMULTANEOUSLY
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
91F. CHN ~ 02 » C02 ~ HN -36.2 C
91R. C02 ~ HM « CHN ~ 02 36.2 C
92F. CHO ~ M * CO + H ~ M 19.& A *
92R. CO ~ H ~ M = CHO + M -19.6 C
93F. CHO *¦ CHO * CH2 ~ C02 -17.3 C
93R. CH2 * C02 = CHO ~ CHO 17.3 C
94F. CHO + CHO a CH20 ~ CO -69.9 B *
94R. CH20 ~ CO = CHO + CHO 69.9 C
95F. CHO ~ CH2 = CH3 + CO -93.0 B *
95R. CH3 ~ CO = CHO + CH2 93.0 C
96F. CHO ~ CH20 = CH3 + C02 -40.3 C
96R. CH3 ~ C02 = CHO + CH20 40.3 C
97F. CHO ~ CH20 * CH30 ~ CO -5.9 C
97R. CH30 + CO = CHO ~ CH20 5.9 C
98F. CHO ~ CH3 * CH2 + CH20 23.0 B ~
98R. CH2 + CH20 « CHO ~ CH3 -23.0 C
99F. CHO ~ CH3 « CH4 + CO -88.6 B ~
99R. CH4 ~ CO * CHO + CH3 88.6 C
100F. CHO ~ CH30 « CH20 ~ CH20 -64.0 C
100R. CH20 ~ CH20 » CHO + CH30 64.0 C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
WEAK BONO FORWARD
THIRO OROER REVERSE
FOUR-CENTER REACTION
STERIC HINDRANCE
WEAK BONO FORWARD
REVERSE ENDOTHERMIC
WEAK BOND FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
LARGE MOLECULES* LOW CONCENTRATIONS
LIKELY TO BE UNIMPORTANT
RETAIN FORWARD FOR COMPARISON WITH
CHO + CH3 « CH4 + CO
LOW CONCENTRATIONS REVERSE
WEAK BOND FORWARD
REVERSE ENDOTHERMIC
LARGE MOLECULES, LOW CONCENTRATIONS
LIKELY TO BE SLOW
-------
REACTION
HR NOTES
IOIF. CHO ~ CH30 = CH4 + C02 -123.0 C
101R. CH4 ~ C02 = CHO + CH30 123.0 C
102F. CHO + CH4 = CH2 ~ CH30 105.7 C
102R. CH2 ~ CH30 = CHO + CH4 -105.7 C
103F. CHO ~ CH4 * CH20 + CH3 18.6 B #
103R. CH20 ~ CH3 = CHO + CH4 -18.6 B *
104F. CHO + H = CH2 + 0 90.6 C
104R. CH2 + 0 * CHO + H -90.6 B *
105F. CHO ~ H ~ M * CH20 ~ M -89.5 C
105R. CH20 ~ M = CHO ~ H + M 89.5 C
106F• CHO ~ H * CO + H2 -88.9 A *
106R. CO + H2 = CHO + H 88.9 C
107F. CHO ~ HN * CH2 + NO 15.4 C
107R. CH2 ~ NO » CHO + HN -15.4 C
108F. CHO ~ HN = CH20 + N -10.6 C
108R. CH20 ~ N = CHO «¦ HN 10.6 C
109F. CHO ~ HN = CN + H20 -53.9 C
109R. CN + H20 * CHO ~ HN 53.9 C
110F. CHO + HNO » CH2 + N02 68.6 C
110R. CH2 + N02 = CHO + HNO -68.6 C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS FUEL RICH
FORWARD ENDOTHERMIC
CONSIDER REVERSE
THIRD ORDER FORWARD
REVERSE ENDOTHERMIC
CONSIDER FORWARD FOR CHO BREAKDOWN
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION
LOW CONCENTRATIONS BOTH DIRECTIONS
LOW CONCENTRATIONS BOTH DIRECTIONS
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
ENOOTHERMIC FORWARD
LOW CONCENTRATIONS REVERSEHO AND CH20
-------
REACTION
HR NOTES
111F. CHO ~ HNO * CH20 ~ NO -36.8 C
111R. CH20 ~ NO » CHO + HNO 36.8 C
112F. CHO + HO * CH2 «• 02 74.9 C
112R. CH2 ~ 02 « CHO «¦ HO -74.9 C
113F. CHO ~ HO * CH20 + 0 16.8 C
113R. CH20 + 0 » CHO * HO -16.8 A ~
114F. CHO ~ HO * CO + H20 -103.8 A ~
114R. CO ~ H20 « CHO + HO 103.8 C
115F. CHO ~ HO * C02 ~ H2 -110.0 C
115R. C02 ~ H2 » CHO + HO 110.0 C
1I6F. CHO ~ H02 * CH20 ~ 02 -39.1 B ~
116R. CH20 ~ 02 » CHO ~ H02 39.1 B *
117F. CHO + H02 « C02 + H20 -165.1 C
117R. C02 ~ H20 « CHO + H02 165.1 C
118F. CHO ~ H2 * CH2 + HO 92.8 C
118R. CH2 + HO s CHO ~ H2 -92.8 C
119F. CHO ~ H2 ¦ CH20 + H 19.0 B *
119R. CH20 ~ H « CHO H2 -19.0 A ~
120F. CHO ~ H2 » CH3 ~ 0 86.5 C
120R. CH3 ~ 0 * CHO ~ H2 -86.5 C
COMMENTS
UNIMPORTANT PATH BETWEEN CHO AND CH20
BETWEEN HNO AND NO
FOUR CENTER REACTION
CHO + HO = CO + H20 FASTER THAN FORWARD
CH2 + 02 = CH20 + 0 FASTER THAN REVERSE
CHO + HO = CO ~ H20 FASTER THAN FORWARD
CONSIDER REVERSE FOR CH20 BREAKDOWN
CONSIDER FORWARO FOR CHO BREAKDOWN
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION
CHO + HO = CO ~ H20 FASTER THAN FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
FOUR-CENTER REACTION
CHO + HQ2 = CH20 * 02 FASTER THAN FWD
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
CH3 + 0 AND CH20 + 0 MORE LIKELY
PRODUCTS FROM REVERSE
CONSIDER BOTH DIRECTIONS
REVERSE MORE LIKELY TO BE IMPORTANT
CH20 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
121F. CHO * H2 ~ M » CH30 + M -6.5 C
121R. CH30 ~ M = CHO + H2 + M 6.5 C
122F. CHO ~ H20 * CH2 + H02 147.8 C
122R. CH2 «¦ H02 » CHC ~ H20 -147.8 C
123F. CHO ~ H20 * CH20 + HO 33.8 C
123R. CH20 ~ HO = CHO ~ H20 -33.8 A *
124F. CHO «• H20 = CH3 ~ 02 85.7 C
124R. CH3 «¦ 02 = CHO + H20 -85.7 C
125F. CHO ~ H20 = CH30 ~ 0 114.6 C
125R. CH30 + 0 » CHO + H20 -114.6 C
126F. CHO ~ N = CN ~ HO -9.5 C
126R. CN ~ HO ¦ CHO * N 9.5 C
127F. CHO + N * CO * HN -59.4 B *
127R. CO ~ HN = CHO + N 59.4 C
128F. CHO ~ NO * CN + H02 78.5 C
128R. CN ~ HO2 » CHO ~ NO -78.5 C
129F• CHO ~ NO = CO ~ HNO -33.2 B *
129R. CO ~ HNO * CHO * NO 33.2 B *
130F. CHO ~ NO - C02 ~ HN -32.7 C
130R. C02 ~ HN s CHO ~ NO 32.7 C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
FORWARD HIGHLY ENDOTHERMIC
CH2 + H02 = CH3 + 02 FASTER THAN REVERSE
CHO ~ M * CO ~ H + M FASTER THAN FORWARD
CONSIDER REVERSE FOR CH20 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS
PROBABLY NOT MAJOR IMPORTANCE
FOUR-CENTER REACTION
CHO + NO = CO + HNO FASTER THAN FORWARO
REVERSE MINOR
-------
REACTION
HR NOTES
131F. CHO + N02 * C02 ~ HNO -85.9 C
131R. C02 ~ HNO » CHO ~ N02 85.9 C
132F. CHO ~ N2 ¦ CN ~ HNO 119.4 C
132R. CN ~ HNO » CHO + N2 -119.4 C
133F. CHO + 0 » CO ~ HO -86.8 A *
133R. CO ~ HO * CHO ~ 0 86.8 C
134F. CHO ~ 0 - C02 + H -107.9 B *
134R. C02 ~ H * CHO ~ 0 107.9 C
135F. CHO ~ 02 » CO ~ H02 -30.8 B *
135R. CO ~ H02 • CHO + 02 30.8 B *
136F. CHO ~ 02 « C02 * HO -92.2 C
136R. C02 ~ HO = CHO + 02 92.2 C
137F. CH2 + CH20 = CH4 ~ CO -111.6 C
137R. CH4 ~ CO ¦ CH2 ~ CH20 111.6 C
138F. CH2 CH30 * CH20 ~ CH3 -87.0 C
138R. CH20 ~ CH3 « CH2 + CH30 87.0 C
139F. CH2 ~ CH4 » CH3 ~ CH3 -4.4 B *
139R. CH3 CH3 ¦ CH2 ~ CH4 4.4 B *
140F. CH2 + C02 * CH20 ~ CO -52.7 C
140R. CH20 ~ CO * CH2 + C02 52.7 C
COMMENTS
FOUR-CENTER
STERIC HINDRANCE
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD FOR CHO BREAKDOWN
REVERSE ENDOTHERMIC
CONSIDER FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
FORWARD FOR CHO BREAKDOWN
REVERSE PROBABLY LESS IMPORTANT
FOUR-CENTER REACTION
CHO + 02 = CO + H02 FASTER THAN FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
UARGE MOLECULES, LOW CONCENTRATIONS
REVERSE ENDOTHERMIC
LIKELY TO BE UNIMPORTANT
CONSIDER BOTH DIRECTIONS FUEL RICH
MAY BE IMPORTANT EARLY STAGES
FORWARD RX UNIMPORTANT FOR CH2 OR C02
REVERSE ENDOTHERMIC
-------
REACTION
HR NOTES
141F. CH2 ~ H ¦+ M * CH3 ~ M -112-5 C
141R. CH3 + M = CH2 + H + M 112.5 C
142F. CH2 ~ HN * CH3 + N -33.6 C
142R. CH3 ~ N = CH2 ~ HN 33.6 C
143F. CH2 + HNO = CH20 + HN -52.2 C
143R• CH20 + HN = CH2 + HNO 52.2 C
144F. CH2 + HNO = CH3 + NO -59.8 C
144R. CH3 + NO « CH2 + HNO 59.8 C
145F. CH2 ~ HNO = CH30 + N 1.2 C
145R. CH30 ~ N * CH2 ~ HNO -1.2 C
146F. CH2 ~ HO * CH20 ~ H -73.8 B *
146R. CH20 ~ H * CH2 ~ HO 73.8 C
147F• CH2 + HO = CH3 ~ 0 -6.2 B *
147R. CH3 + 0 » CH2 ~ HO 6.2 B *
148F• CH2 ~ HO ~ M = CH30 + M -99.3 C
148R. CH30 ~ M « CH2 + HO + M 99.3 C
149F. CH2 ~ HO2 « CH20 ~ HO -114.0 C
149R. CH20 + HO = CH2 ~ H02 114.0 C
150F. CH2 + H02 = CH3 + 02 -62.2 B *
150R. CH3 ~ 02 * CH2 + H02 62.2 C
COMMENTS
THIRD ORDER, LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS BOTH DIRECTIONS
CH2 + HNO = CH3 + NO MORE LIKELY FORWARD
REVERSE ENDOTHERMIC
FORWARD RX UNIMPORTANT FOR CH2 OR HNO
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
REVERSE FOR CH3 BREAKDOWN
CH20 ~ H OR CH3 + 0 MORE LIKELY PRODUCTS
REVERSE ENDOTHERMIC
CH2 ~ H02 = CH3 + 02 MORE LIKELY FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD
REVERSE ENDOTHERMIC
-------
REACTION
HR NOTES
151F. CH2 + H02 * CH30 + 0 -33.2 C
151R. CH30 ~ 0 * CH2 + H02 33.2 C
152F. CH2 ~ H2 * CH3 ~ H -4.1 B *
152R. CH3 ~ H = CK2 + H2 4.1 A *
153F. CH2 ~ H2 ~ M = CH4 ~ M -112.2 C
153R. CH4 + M « CH2 + H2 «¦ M 112.2 C
154F. CH2 ~ H20 ¦ CH20 + H2 -58.9 C
154R. CH20 ~ H2 » CH2 ~ H20 58.9 C
155F. CH2 ~ H20 » CH3 * HO 10.8 B ~
155R. CH3 + HO = CH2 ~ H20 -10.8 A *
156F. CH2 ~ H20 » CH30 + H 24.0 C
156R. CH30 ~ H ® CH2 ~ H20 -24.0 C
157F. CH2 + H20 « CH4 ~ 0 9.0 C
157R. CH4 + 0 = CH2 + H20 -9.0 C
158F. CH2 ~ N * CN ~ H2 -102.3 C
158R. CN + H2 s CH2 ~ N 102.3 C
159F. CH2 + NO a CH20 ~ N -26.0 B *
159R. CH20 ~ N * CH2 + NO 26.0 C
160F. CH2 + NO = CN ~ H20 -69.3 C
160R. CN ~ H20 » CH2 + NO 69.3 C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER BOTH DIRECTIONS
REVERSE FOR CH3 BREAKDOWN FUEL RICH
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
MIGHT BE FOUR-CENTER STERICALLY HINDERED
CONSIDER BOTH DIRECTIONS
REVERSE FOR CH3 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD FUEL RICH
REVERSE NOT LIKELY TO BE IMPORTANT
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
161F. CH2 ~ N02 = CH20 ~ NO -105.4 C
161R. CH20 + NO = CH2 + N02 105.4 C
162F. CH2 + N20 = CH20 * N2 -140.2 C
162R. CH20 ~ N2 » CH2 + N20 140.2 C
163F. CH2 ~ 0 ~ M = CH20 M -180.1 C
163R. CH20 + M * CH2 + 0 + H 180.1 C
164F. CH2 + 0 = CO + H2 -179.5 C
164R. CO + H2 = CH2 + 0 179.5 C
165F• CH2 ~ 02 = CH20 + 0 -58.1 B *
165R. CH20 ~ 0 » CH2 + 02 58.1 C
166F. CH2 + 02 = CO + H20 -178.6 C
166R. CO + H20 « CH2 + 02 178.6 C
167F. CH2 ~ 02 = C02 + H2 -184.9 C
167R. C02 ~ H2 = CH2 + 02 184.9 C
168F. CH20 ~ M = CO H2 ~ M 0.6 C
168R. CO + H2 + M = CH20 + M -0.6 C
169F. CH20 * CH20 = CH4 + C02 -59.0 C
169R. CH4 C02 = CH20 + CH20 59.0 C
170F. CH20 * CH4 » CH3 ~ CH30 82.7 C
170R. CH3 + CH30 = CH20 CH4 -82.7 C
COMMENTS
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
THIRD ORDER FORWARD
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
FORWARD ENOOTHERMIC
LARGE MOLECULES LOW CONCENTRATIONS REV
-------
REACTION
HR NOTES
171F. CH20 + H * CH3 * 0 67.6 C
171R. CH3 ~ 0 = CH20 + H -67.6 A ~
172F. CH20 «¦ H + M * CH30 + M -25.5 B *
172R. CH30 ~ M » CH?0 + H -f M 25.5 B *
173F. CH20 ~ HN = CH3 ~ NO -7.6 C
173R. CH3 ~ NO * CH20 + HN 7.6 C
174F. CH20 ~ HN « CH30 + N 53.4 C
174R. CH30 ~ N « CH20 «• HN -53.4 B ~
175F. CH20 ~ HNO = CH3 ~ N02 45.6 C
175R. CH3 ~ N02 » CH20 + HNO -45.6 C
176F. CH20 ~ HNO * CH30 + NO 27.2 C
176R. CH30 ~ NO = CH20 + HNO -27.2 C
177F. CH20 ~ HO * CH3 + 02 51.8 C
177R. CH3 ~ 02 » CH20 + HO -51.8 B *
178F« CH20 ~ HO » CH30 +0 80.8 C
178R. CH30 + 0 * CH20 ~ HO -80.8 B ~
179F. CH20 ~ H02 « CH30 + 02 24.9 C
179R. CH30 ~ 02 » CH20 ~ H02 -24.9 B *
180F. CH20 + H2 * CH3 + HO 69.7 C
180R. CH3 ~HO* CH20 + H2 -69.7 C
COMMENTS
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH3 BREAKDOWN
CONSIDER BOTH DIRECTIONS
REVERSE MAY BE IMPORTANT CH30 BREAKDOWN
FOUR-CENTER* STERIC HINDRANCE
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH30 BREAKDOWN
PROBABLY MINOR
FOUR-CENTER, STERIC HINDRANCE
LOW CONCENTRATIONS BOTH DIRECTIONS
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH3 BREAKDOWN
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH30 BREAKDOWN
LOW CONCENTRATIONS FORWARD
CONSIDER REVERSE FOR CH30 BREAKDOWN
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC'
CH3 ~ HO = CH4 + 0 AND
CH3 + HO = CH2 + H20 MORE LIKELY REVERSE
-------
REACTION
HR NOTES
181F. CH20 + H2 = CH30 + H 83.0 C
181R. CH30 + H = CH20 ~ H2 -83.0 B *
182F. CH20 ~ H2 = CH4 ~ 0 67.9 C
182R. CH4 ~ 0 = CH20 + H2 -67.9 C
183F. CH20 «• H20 ¦ CH3 + H02 124.8 C
183R. CH3 ~ H02 » CH20 ~ H20 -124.8 C
184F. CH20 ~ H20 = CH30 + HO 97.8 C
184R. CH30 ~ HO = CH20 + H20 -97.8 B *
185F. CH20 + H20 = CH4 + 02 67.0 C
185R. CH4 ~ 02 = CH20 ~ H20 -67.0 C
186F. CH20 ~ N = CN ~ H20 -43.3 C
186R. CN + H20 = CH20 «¦ N 43.3 C
187F. CH20 ~ 0 = CO + H20 -120.6 C
187R* CO ~ H20 * CH20 + 0 120.6 C
188F. CH20 ~ 0 = C02 * H2 -126.8 C
188R. C02 ~ H2 = CH20 + 0 126.8 C
189F. CH20 ~ 02 * C02 ~ H20 -126.0 C
189R* C02 «¦ H20 » CH20 + 02 126.0 C
190F. CH3 ~ C02 = CH30 «¦ CO 34.4 C
190R. CH30 ~ CO ¦ CH3 + C02 -34.4 C
COMMENTS
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH30 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION
STERIC HINDRANCE
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR CH30 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
LARGE MOLECULES
LIKELY TO BE UNIMPORTANT
-------
REACTION
HR NOTES
191F. CH3 + H ~ H » CH4 ~ M -108.2 B *
191R. CH4 ~ M « CH3 + H + M 108.2 B *
192F. CH3 ~ HN s CH4 ~ N -29.2 C
192R- CH4 ~ N = CH3 + HN 29.2 C
193F. CH3 + HNO = CH30 + HN 34.8 C
193R. CH30 ~ HN - CH3 ~ HNO -34.8 C
194F. CH3 ~ HNO = CH4 + NO -55.4 C
194R. CH4 + NO » CH3 + HNO 55.4 C
195F. CH3 ~ HO s CH30 + H 13.2 B ~
195R. CH30 H = CH3 + HO -13.2 B *
196F. CH3 ~ HO » CH4 + 0 -1.8 A *
196R. CH4 ~ 0 * CH3 ~ HO 1.8 A *
197F. CH3 ~ H02 » CH30 + HO -27.0 C
197R. CH30 «¦ HO = CH3 4 HO2 27.0 C
198F. CH3 ~ H02 = CH4 ~ 02 -57.8 B ~
198R. CH* ~ 02 « CH3 + H02 57.8 C
199F. CH3 ~ H2 » CH4 + H 0.3 A ~
I99R. CH4 H * CH3 ~ H2 -0.3 A *
200F. CH3 ~ H20 » CH30 + H2 28.1 C
200R. CH30 ~ H2 = CH3 + H20 -28.1 C
COMMENTS
MAY BE IMPORTANT EARLY STAGES
LOW CONCENTRATIONS
LOW CONCENTRATIONS
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS FOR ROLE CH30
CONSIDER BOTH DIRECTIONS
ROLE IN INITIAL CH4 BREAKDOWN
CH3 ~ H02 = CH4 + 02 MORE LIKELY FORWARD
CH30 ~ HO = CH20 + H20 MORE LIKELY REV
CONSIDER FORWARD
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
ROLE IN INITIAL CH4 BREAKDOWN
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
201F. CH3 * H20 = CH4 + HO 15.2 A ~
201R. CH4 + HO « CH3 + H20 -15.2 A *
202F. CH3 + NO 8 CH30 ~ N 61.0 C
202R. CH30 + N » CH3 + NO -61.0 C
203F. CH3 + N02 * CH30 + NO -18.3 C
203R. CH30 + NO « CH3 + N02 18.3 C
204F• CH3 + N20 = CH30 + N2 -53.2 C
204R. CH30 ~ N2 « CH3 ~ N20 53.2 C
2-05F. CH3 + 0 + M = CH30 ~ M -93.1 C
205R. CH30 + M = CH3 + 0 + M 93.1 C
206F. CH3 ~ 02 = CH30 + 0 29.0 B *
206R. CH30 + 0 = CH3 + 02 -29.0 B *
207F. CH30 ~ H * CH4 ~ 0 -15.1 C
207R. CH4 ~ 0 = CH30 * H 15.1 C
208F• CH30 ~ HN = CH4 ~ NO -90.3 C
208R. CH4 ~ NO s CH30 + HN 90.3 C
209F. CH30 ~ HNO * CH4 + N02 -37.1 C
209R. CH4 ~ N02 = CH30 ~ HNO 37.1 C
210F• CH30 ~ HO s CH4 ~ 02 -30.8 C
210R. CH4 + 02 = CH30 ~ HO 30.8 C
COMMENTS
CONSIDER BOTH DIRECTIONS
ROLE IN INITIAL CH4 BREAKDOWN
FORWARD ENDOTHERMIC
CH30 + N = CH20 + HN MORE LIKELY REVERSE
LOW CONCENTRATIONS BOTH DIRECTIONS
LARGE MOLECULES STERIC HINDRANCE FORWARO
REVERSE ENDOTHERMIC
THIRD ORDER FORWARD
STABILIZATION UNLIKELY
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
FORWARD FOR CH3 BREAKDOWN
CH30 + H = CH20 + H2 MORE LIKELY FORWARD
CH4 + 0 = CH3 + HO MORE LIKELY REVERSE
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
LOW CONCENTRATIONS BOTH DIRECTIONS
FOUR-CENTERf STERIC HINDRANCE
FOUR-CENTER, STERIC HINDRANCE
-------
REACTION
HR NOTES
211F. CH30 ~ H2 = CH4 ~ HO -12.9 C
2lift* CH4 + HO s CH30 ~ H2 12.9 C
212F. CH30 ~ H20 = CH4 ~ H02 42.1 C
212R. CH4 ~ H02 = CH30 ~ H20 -42.1 C
213F. CM ~ HO = CO ~ HN -49.9 C
213R. CO ~ HN = CN + HO 49.9 C
214F. CN «• H02 * CO ~ HNO -111.7 C
214R. CO ~ HNO ¦ CN ~ H02 111.7 C
215F. CN ~ H02 « C02 + HN -111.2 C
215R. C02 ~ HN « CN + H02 111.2 C
216F. CN + NO » CO ~ N2 -152.6 B *
216R. CO + M2 a CN + NO 152.6 C
217F. CN ~ N02 » CO + N20 -117.7 C
217R. CO ~ N20 * CN ~ N02 117.7 C
218F. CN + N02 * C02 ~ N2 -205.3 C
218R. C02 ~ N2 * CN ~ N02 205.3 C
219F. CN ~ 0 - CO ~ N -77.2 B ~
219R. CO + N « CN ~ 0 77.2 C
220F. CN ~ 02 » CO ~ NO -109.3 B *
220R. CO ~ NO « CN * 02 109.3 C
COMMENTS
FOUR-CENTER, STERIC HINDRANCE
FOUR-CENTER, STERIC HINDRANCE
FOUR-CENTER REACTION
CN + HO = CHN + 0 MORE LIKELY FORWARD
REVERSE ENOOTHERMIC
FOUR-CENTER FOR NOH STRUCTURE
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD FOR NO DESTRUCTION
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION
FOUR-CENTER, STERIC HINDRANCE
REVERSE HIGHLY ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
CONSIDER FORWARD
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION, PROBABLY SLOW
REVERSE HIGHLY ENDOTHERMIC
-------
REACTION
HR NOTES
221F. CN + 02 = C02 ~ N -82.6 C
221R. C02 + N = CN ~ 02 82.6 C
222F. CO * HNO » C02 ~ HN 0.4 C
222R. C02 ~ HN = CO + HNO -0.4 C
223F. CO ~ HO * C02 + H -21.1 A *
223R. C02 «¦ H = CO ~ HO 21.1 B *
224F. CO ~ H02 * C02 ~ HO -61.3 C
224R. C02 + HO ¦ CO + H02 61.3 C
225F. CO ~ H20 = C02 + H2 -6.3 C
225R. C02 + H2 = CO + H20 6.3 C
226F. CO ~ NO « C02 + N 26.7 C
226R. C02 ~ N « CO ~ NO -26.7 C
227F. CO + N02 « C02 ~ NO -52.7 C
227R. C02 ~ NO » CO + N02 52.7 C
228F. CO ~ N20 = C02 ~ N2 -87.6 C
228R. C02 + N2 = CO ~ N20 87.6 C
229F. CO «¦ 0 + M = C02 + M -127.4 B *
229R. C02 ~M«C0+0+M 127.4 C
230F. CO ~ 02 * C02 ~ 0 -5.4 B *
230R. C02 «¦ 0 = CO ~ 02 5.4 B *
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
HNOt HN MINOR RX PARTNERS FOR CO, C02
FORWARD MAIN PATH FROM CO TO C02
CONSIDER BOTH DIRECTIONS
CO ~ HO « C02 + H MORE IMPORTANT FORWARD
MAY HAVE MINOR ROLE FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
SPIN HINDERED
EXPERIMENT INDICATES REACTION SLOW
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
CO, N20 MINOR REACTION PARTNERS
REVERSE ENDOTHERMIC
FORWARD TERMINATION REACTION
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
PROBABLY SLOWER THAN CO ~ HO = C02 ~ H
-------
REACTION
HR NOTES
231F. H+H+M=H2+M -108.4 A *
231R. H2+M*H+H+M 108.4 C
232F• H + HN » H2 ~ N -29.5 B *
232R. H2 ~ N » H + HN 29.5 B *
233F. H ~ HNO » HN ~ HO 21.6 B *
233R. HN + HQ * H ~ HNO -21.6 B *
234F. H ~ HNO « H2 ~ NO -55.7 B *
234R. H2 ~ NO = H * HNO 55.7 C
235F. H ~ HNO « H20 ~ N -22.8 C
235R. H20 + N = H ~ HNO 22.8 C
236F. H ~ HO = H20 + 0 -2.2 A *
236R. H20 + 0 « H HQ 2.2 A ~
237F. H * HO ~ H s H20 + M -123.3 A *
237R. H20 ~M«H«-HO*M 123.3 C
238F. H ~ H02 « HO ~ HO -40.2 B »
238R. HO + HO « H ~ H02 40.2 C
239F. H + H02 « H2 + 02 -58.1 B *
239R. H2 ~ 02 = H ~ H02 58.1 C
240F. H ~ H02 * H20 ~ 0 -57.2 C
240R. H20 ~ 0 = H + HO2 57.2 C
COMMENTS
FORWARD TERMINATION REACTION
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
CONSIDER BOTH DIRECTIONS
PROBABLY MINOR
CONSIDER FORWARD, PROBABLY MINOR
REVERSE ENDOTHERMIC
POSSIBLE FOR NOH STRUCTURE
PROBABLY MINOR
CONSIDER BOTH DIRECTIONS
FORWARD TERMINATION REACTION
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD FOR H02 REMOVAL
HO + HO = H20 + 0 FASTER THAN REVERSE
CONSIDER FORWARD FOR H02 REMOVAL
REVERSE ENDOTHERMIC
FORWARD PRODUCTS MORE LIKELY TO 8E
HO + HO OR H2 + 02
-------
REACTION HR NOTES
241F. H ~ H20 ¦ HO H2 14.9 A *
241R. HO ~ H2 » H ~ H20 -14.9 A *
242F. H + N + H = HN + H -78.9 C
242R. HN + H ® H + M ~ H 78.9 C
243F. H ~ NO * HN ~ 0 75.9 C
243R. HN ~ 0 = H ~ NO -75.9 B *
244F. H + NO + H a HNO ~ M -52.7 C
244R. HNO ~M»H*NO+M 52.7 C
245F. H ~ NO » HO ~ N 47.8 B *
245R. HO + N = H + NO -47.8 A ~
246F. H ~ N02 * HN ~ 02 27.9 C
246R. HN + 02 » H + N02 -27.9 C
247F. H ~ N02 = HNO + 0 22.0 C
247R. HNO ~ 0 = H + N02 -22.0 C
248F. H ~ N02 « HO ~ NO -31.6 B *
248R. HO ~ NO * H ~ N02 31.6 B ~
249F. H ~ N02 = H02 + N 56.4 C
249R. H02 ~ N ¦ H ~ N02 -56.4 C
250F. H ~ N2 * HN ~ N 150.5 C
250R. HN + N « H ~ N2 -150.5 C
COMMENTS
CONSIDER BOTH DIRECTIONS
THIRD ORDER* LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
FORWARD ENDOTHERMIC
CONSIDER REVERSE
THIRD ORDER FORWARD
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
REVERSE PART OF MODIFIED ZELDOVICH
STERIC HINDRANCE
OTHER PRODUCTS MORE LIKELY
POSSIBLE FOR NOH STRUCTURE
OTHER PRODUCTS MORE LIKELY
CONSIDER BOTH DIRECTIONS
PROBABLY UNIMPORTANT
NOT LIKELY TO BE ELEMENTARY REACTION
FORWARD HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
-------
REACTION
HR NOTES
251F. H ~ N20 * HN ~ NO 36.2 C
251R. HN ~ NO = H ~ N20 -36.2 C
252F. H + N20 « HNO ~ N 62.5 C
252R. HNO ~ N = H * N20 -62.5 C
253F. H ~ N20 - HO ~ N2 -66.4 B *
253R. HO + N2 s H ~ N20 66.4 C
254F. H 0 ~ M = HO + M -106.3 A *
254R. H0+M*H+0+M 106.3 C
255F. H ~ 02 * HQ ~ 0 15.7 A *
255R. HO + 0 = H ~ 02 -15.7 A *
256F. H + 02 + M = H02 ~ M -50.4 B ~
256R. H02 ~ M' * H + 02 + N 50.4 C
257F. HN ~ HN = H2 ~ N2 -180.0 C
257R. H2 ~ N2 » HN ~ HN 180.0 C
258F. HN ~ HNO » H2 + N20 -92.0 C
258R. H2 ~ N20 • HN ~ HNO 92.0 C
259F. HN + HNO =» H20 + N2 -173.3 C
259R. H20 ~ N2 s HN + HNO 173.3 C
260F. HN ~ HO ¦ H2 + NO -77.3 C
260R. H2 ~ NO = HN + HO 77.3 C
COMMENTS
H ~ N20 = HO + N2 FASTER FORWARD
LOW CONCENTRATIONS REVERSE
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
CONSIDER FORWARD
REVERSE ENDOTHERMIC
FORWARD REMOVES ACTIVE CENTERS
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
CONSIDER FORWARD
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER, STERIC HINDRANCE
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
FOUR-CENTER, STERIC HINDRANCE
FOUR-CENTER REACTION
HN ~ HO = H20 + N MORE LIKELY FORWARD
REVERSE ENDOTHERMIC
-------
REACTION
HR NOTES
261F. HN + HO ® H20 ~ N -44.4 B *
261R. H20 ~ N = HN + HO 44.4 C
262F. HN + H02 * HNO + HO -61.8 C
262R. HNO + HO * HN ~ H02 61.8 C
263F. HN ~ H02 » H2 + N02 -86.0 C
263R. H2 ~ N02 = HN ~ H02 86.0 C
264F. HN + H02 * H20 ~ NO -132.4 C
264R. H20 + NO = HN + H02 132.4 C
265F• HN + H20 * HNO * H2 -6.7 C
265R. HNO ~ HZ s HN + H20 6.7 C
266F. HN +.N0 = HNO + N 26.2 C
266R. HNO ~ N » HN + .N0 -26.2 C
267F. HN + NO » HO ~ N2 -102.7 C
267R. HO ~ N2 » HN + NO 102.7 C
268F. HN + N02 * HNO ~ NO -53.2 C
268R. HNO ~ NO » HN * N02 53.2 C
269F. HN ~ N02 = HO ~ N20 -67.8 C
269R. HO + N20 » HN ~ N02 67.8 C
270F. HN ~ N02 » H02 + N2 -94.0 C
270R. H02 ~ N2 ¦ HN ~ N02 94.0 C
COMMENTS
CONSIOER FORWARD
REVERSE ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION, STERIC HINDRANCE
FOUR-CENTER REACTION STERIC HINDRANCE
NOH STRUCTURE
LOW CONCENTRATIONS BOTH DIRECTIONS
FOUR-CENTER REACTION
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
LOW CONCENTRATIONS BOTH DIRECTIONS
FOUR-CENTER REACTION, STERIC HINDRANCE
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
271F. HN + N20 » HNO + N2 -88.0 C
271R. HNO ~ N2 ¦ HN ~ N20 88.0 C
272F. HN ~ 0 + M * HNO + M -127.9 C
272R. HNO + M = HN ~ 0 ~ M 127.9 C
273F. HN + 0 « HO * N -27.4 C
273R. HO ~ N * HN ~ 0 27.4 C
274F. HN ~ 02 * HNO + 0 -5.8 B *
274R. HNO + 0 * HN + 02 5.8 8 *
275F. HN ~ 02 a HQ + NO -59.4 C
275R. HO ~ NO = HN + 02 59.4 C
276F. HN + 02 = H02 + N 28.6 C
276R. H02 + N * HN ~ 02 -28.6 C
277F. HNO +H®HO+N+H 100.5 C
277R. HO + N ~ M - HNO * M -100.5 C
278F. HNO + HNO - H20 ~ N20 -85.3 C
278R. H20 + N20 * HNO + HNO 85.3 C
279F. HNO + HO » H2 ~ N02 -24.2 C
279R. H2 + N02 * HNO ~ HO 24.2 C
280F. HNO ~ HO « H20 ~ NO -70.6 B *
280R. H20 * NO =* HNO ~ HO 70.6 C
COMMENTS
LOW CONCENTRATIONS FORWARD
REVERSE ENOOTHERMIC
THIRO ORDER FORWARD
REVERSE HIGHLY ENOOTHERMIC
HN ~ 0 s H + NO MORE LIKELY FORWARD
HO + N = H + NO MORE LIKELY REVERSE
CONSIDER BOTH DIRECTIONS
PROBABLY MINOR
FOUR-CENTER REACTION
HN + 02 = HNO + 0 FASTER FORWARD
REVERSE ENDOTHERMIC
HN + 02 = HNO + 0 FASTER FORWARD
LOW CONCENTRATIONS REVERSE
FORWARD HIGHLY ENDOTHERMIC
THIRD ORDER REVERSE
NOH STRUCTURE
FOUR-CENTER REACTION, STERIC HINDRANCE
FOUR-CENTER REACTION
HNO + HO = H20 ~ NO MORE LIKELY FORWARD
LOW CONCENTRATIONS REVERSE
CONSIDER FORWARD
REVERSE ENDOTHERMIC
-------
REACTION
HR NOTES
281F. HNO ~ H02 = H20 + N02 -79.2 C
281R. H20 ~ N02 = HNO ~ H02 79.2 C
282F. HNO + N * HO ~ N2 -128.9 C
282R. HO ~ N2 = HNO + N 128.9 C
283F. HNO + NO = HO ~ N20 -14.7 C
283R. HO ~ N20 ¦ HNO + NO 14.7 C
284F. HNO ~ NO » H02 ~ N2 -40.9 C
284R. H02 ~ N2 = HNO + NO 40.9 C
285F. HNO + N02 = H02 ~ N20 -6.0 C
285R. H02 + N20 = HNO N02 6.0 C
286F. HNO ~ 0 = HO + NO -53.6 B *
286R. HO + NO = HNO + 0 53.6 C
287F. HNO ~ 0 = H02 + N 34.4 C
287R. H02 + N = HNO ~ 0 -34.4 C
£88F. HNO + 02 = HO + N02 -6.3 C
288R. HO ~ N02 « HNO + 02 6.3 C
289F. HNO + 02 » H02 + NO 2.4 C
289R. H02 NO s HNO + 02 -2.4 C
290F. HO + HO = H2 «¦ 02 -17.9 C
290R. H2 ~ 02 = HO ~ HO 17.9 C
COMMENTS
FOUR-CENTER REACTION, STERIC HINDRANCE
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
FOUR-CENTER REACTION, STERIC HINDRANCE
FOUR-CENTER REACTION, NOH STRUCTURE
LOW CONCENTRATIONS FORWARD
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION, STERIC HINDRANCE
CONSIDER FORWARD
REVERSE ENDOTHERMIC
HNO + 0 = HO + NO FASTER FORWARD
LOW CONCENTRATIONS REVERSE
FOUR-CENTER REACTION, STERIC HINDRANCE
FOUR-CENTER REACTION, STERIC HINDRANCE
FOUR-CENTER REACTION
HO ~ HO = H20 + 0 FASTER FORWARD
REVERSE MAY HAVE ROLE IN H2/02 IGNITION
-------
REACTION
HR NOTES
291F. HO ~ HO = H20 ~ 0 -17.0 A *
291R. H20 ~ 0 =» HO ~ HO 17.0 A ~
292F. HO + H02 = H20 02 -73.0 A *
292R. H20 ~ 02 = HG * H02 73.0 C
293F. HO * H20 = H02 ~ H2 55.X C
29"*. H02 + H2 « HO ~ H20 -55.1 C
294F. HO + NO * H02 ~ N 88.0 C
294R. H02 ~ N ¦ HO ~ NO -88.0 C
295F. HO ~ N02 * H02 ~ NO 8.6 B *
295R. H02 ~ NO ¦ HO ~ N02 -8.6 B *
296F. HO ~ N20 ¦ H02 ~ N2 -26.2 B *
296R. H02 ~ N2 = HO ~ N20 26.2 B *
297F. HO + 0 + M = H02 ~ M -66.1 B *
297R. H02 + H » HO ~ 0 ~ H 66.1 C
298F. HO + 02 = H02 ~ 0 55.9 C
298R. H02 ~ 0 * HO ~ 02 -55.9 A *
299F. H2 + NO » H20 ~ N 32.9 C
299R. H20 + N * H2 ~ NO -32.9 C
300F. H2 + N02 - H20 + NO -46.4 C
300R. H20 + NO ¦ H2 ~ N02 46.4 C
COMMENTS
CONSIDER BOTH DIRECTIONS
CONSIDER FORWARD FOR H02 REMOVAL
REVERSE ENDOTHERMIC
FOUR-CENTER REACTION
FORWARD ENDOTHERMIC
FORWARD ENDOTHERMIC
LOW CONCENTRATIONS REVERSE
CONSIDER BOTH DIRECTIONS
REVERSE HAS BEEN CONSIDERED FOR
EARLY N02 FORMATION
CONSIDER BOTH DIRECTIONS
PROBABLY MINOR
CONSIDER FORWARD
REVERSE ENDOTHERMIC
FORWARD ENDOTHERMIC
CONSIDER REVERSE FOR H02 REMOVAL
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
-------
REACTION
HR NOTES
301F. H2 + N20 - H20 + N2 -81.3 C
301R. H20 ~ N2 = H2 + N20 81.3 C
302F. H2 + 0 + M = H20 * M -121.2 C
302R. H20 ~ H » H2 » 0 + M 121.2 C
303F. H2 + 02 • H20 ~ 0 0.9 C
303R. H20 ~ 0 « H2 '~ 02 -0.9 C
304F• N+N+M=N2+M -229.4 C
304R. N2+M*N+N+M 229.4 C
305F. N ~ NO = N2 ~ 0 -75.3 8 ~
305R. N2 ~ 0 = N + NO 75.3 A ~
306F• N + NO ~ M = N20 + M -115.2 C
306R. N20 ~ M * N ~ NO ~ M 115.2 C
307F• N ~ N02 * NO + NO -79.4 B ~
307R. NO ~ NO = N + N02 79.4 C
308F. N ~ N02 * N2 ~ 02 -122.6 C
308R. N2 ~ 02 * N ~ N02 122.6 C
309F. N ~ N02 = N20 ~ 0 -40.4 C
309R. N20 * 0 = N + N02 40.4 C
310F. N ~ N20 = NO N2 -114.2 C
310R. NO + N2 = N ~ N20 114.2 C
COMMENTS
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
NOT LIKELY TO BE ELEMENTARY REACTION
THIRD ORDER, LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
REVERSE PART OF ZELDOVICH MECHANISM
THIRD ORDER, LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
CONSIDER FORWARD (LOW CONCENTRATIONS J
REVERSE ENDOTHERMIC
NOT LIKELY TO BE ELEMENTARY REACTION
N + N02 s NO ~ NO MORE LIKELY FORWARD
REVERSE ENDOTHERMIC
LOW CONCENTRATIONS FORWARD
REVERSE HIGHLY ENDOTHERMIC
-------
REACTION
HR NOTES
311F. N+0*H»N0+H -154.1 C
311R. N0+M*N+0+M 154.1 C
312F. N ~ 02 » NO ~ 0 -32.1 A *
312R. NO ~ 0 » N ~ 02 32.1 B *
313F. N ~ 02 ~ M » N02 ~ M -106.8 C
313R. N02 ~M*N+02+M 106.8 C
314F. NO ~ NO * N2 «• 02 -43.2 C
314R. N2 * 02 * NO ~ NO 43.2 C
315F. NO + NO * N20 ~ 0 38.9 B *
315R. N20 ~ 0 * NO + NO -38.9 B *
316F. NO ~ N02 « N20 ~ 02 -8.4 C
316R. N20 ~ 02 = NO ~ N02 8.4 C
317F. NO + N20 * N02 ~ N2 -34.9 C
317R. N02 ~ N2 ¦ NO ~ N20 34.9 C
318F. NO ~ 0 ~ M ¦ N02 + M -74.7 B *
318R. N02 +M-N0+0+M 74.7 C
319F. NO + 02 3 N02 ~ 0 47.3 B *
319R. N02 + 0 - NO + 02 -47.3 B ~
320F. N2 ~ 0 ~ M ¦ N20 ~ M -39.9 B ~
320R. N20 ~ H s N2 + 0 + H 39.9 B ~
COMMENTS
THIRD ORDER, LOW CONCENTRATION FORWARD
REVERSE HIGHLY ENOOTHERMIC
CONSIOER BOTH DIRECTIONS
FORWARD PART OF ZELDOVICH MECHANISM
NOT LIKELY TO BE ELEMENTARY REACTION
FOUR-CENTER REACTION, SPIN HINDERED
NO + NO = N20 + 0 FASTER EXPERIMENTALLY
POSSIBLY BY AT LEAST A FACTOR OF 10
CONSIDER BOTH DIRECTIONS
NOT LIKELY TO BE ELEMENTARY REACTION
FORWARD SLOW EXPERIMENTALLY
REVERSE EVEN SLOWER
CONSIDER FORWARD
REVERSE ENDOTHERMIC
CONSIDER BOTH DIRECTIONS
FORWARD ENDOTHERMIC
CONSIDER BOTH DIRECTIONS FOR ROLE OF N20
-------
REACTION
321F. N2 + 02 = N20 + 0
321R. N20 + 0 = N2 + 02
HR NOTES
82.2 C
82.2 B *
322F. 0+0+M=0?+M
322R. 02*M«0+0+M
-122.0
122.0
A *
C
COMMENTS
FORWARD ENDOTHERMIC
CONSIDER REVERSE
FORWARD TERMINATION REACTION
REVERSE HIGHLY ENDOTHERMIC
-------
FIGURE C-l
MAJOR KINETIC PATHS FOR METHANE AIR COMBUSTION COUPLED TO NO^ FORMATION
STIRRED REACTOR, 80% STOICHIOMETRIC AIR, r = 2 msec A
LEGEND
Numbers at tail of arrow indicated percentage
of destruction of species by indicated reaction
Numbers at head of arrow indicate percentage
of production of species by indicated reaction
(Input and output of reactor not included)
Reactants and products (circled) indicated
at arrows.
-------
FIGURE C-2
MAJOR KINETIC PATHS FOR METHANE AIR COMBUSTION COUPLED TO NO„ FORMATION
STIRRED REACTOR, 100% STOICHIOMETRIC AIR, t » 2 msec
16 79
LEGEND
Numbers at tail of arrow indicated percentage
of destruction of species by indicated reaction
Numbers at head of arrow indicate percentage
of production of species by indicated reaction
(Input and output of reactor not included)
Reactants and products (circled) indicated
at arrows.
-------
FIGURE C-3
MAJOR KINETIC PATHS FOR METHANE AIR COMBUSTION COUPLED TO NO„ FORMATION
STIRRED REACTOR, 125% STOICHIOMETRIC AIR, T « 2 msec A
LEGEND
Numbers at tail of arrow indicated percentage
of destruction of species by indicated reaction
Numbers at head of arrow indicate percentage
of production of species by indicated reaction
(Input and output of reactor not included)
Reactants and products (circled) indicated
at arrows.
a
i
10
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D-l
TECHNICAL REPORT DATA
(Please read Iniiruetions on I he reverse before eomp i
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