EPA-AA-SDSB-82-12

                    Technical Report
         Characterization of  a  Heavy-Duty Diesel
     Engine Modified for Operation on Neat Methanol
                           By

                       Randy  Jones


                        June  1982
                         NOTICE

Technical  Reports  do  not  necessarily  represent  final  EPA
decisions  or   positions.    They  are  intended   to   present
technical analysis  of  issues using  data  which are  currently
available.  The purpose  in  the  release of such reports  is  to
facilitate  the  exchange  of  technical  information  and  to
inform  the  public  of  technical developments  which may  form
the basis  for a  final  EPA decision,  position or  regulatory
action.

        Standards Development and Support  Branch
          Emission Control Technology Division
      Office  of  Mobile Source Air Pollution Control
           Office of Air, Noise and Radiation
          U.  S.  Environmental Protection Agency

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I.   Introduction

     Because  of  the  increased  interest  in  methanol as  a  motor
vehicle fuel, EPA's  Office  of Mobile Source Air  Pollution  Control
(OMSAPC) has  initiated a  vehicle  and  engine  testing program  to
characterize  the emissions  and  performance  of  the  most  likely
methanol applications.   In  one  study  an International  Harvester
DT-466B  heavy-duty   diesel  engine  was  modified  and  subsequently
tested on diesel fuel and on neat  methanol.   This report  describes
the conductance and results of the study.

II.  Background

     The growing dependence  of many countries  on  unstable  supplies
of imported petroleum has created  a need to  evaluate the use  of
alternative  fuels.    One  of  the  most  promising  and  extensively
studied alternate fuels is methanol.

     Methanol  is  well  suited  for  use  in   the   fuel-inducted,
spark-ignition  (SI)  engine  and  much  research and  attention  has
been  concentrated   in  this   area.   Methanol  has  been  generally
disregarded  for use in  the  fuel-injected,  compression-ignition
(CI) engine,  because its  low  cetane  properties make  it  difficult
to  compression-ignite.    However,  if   an   ignition  source   is
provided, methanol's combustion  properties are  such  that it  can be
used  in the   traditional  CI engine  and  potentially  result  in
environmental  benefits when  compared  to  diesel  fuel  or  other
alternate fuels.

     Methanol1s  high  octane   rating   allows   for  the   higher
compression  ratios,  hence  higher  thermal   efficiencies,   of  SI
engines.  Methanol  use in  the CI  engine  would take  advantage  of
the   inherently   better  efficiency   of   unthrottled   operation.
Methanolfs  ability to  burn  at lower flame temperatures  contribute
to  better  efficiency  and   lower  NOx   emissions.    The   organic
emissions from methanol combustion  are primarily  unburned fuel and
aldehydes,   which   are   controllable  with   standard   oxidation
catalysts.    Since  methanol   fuel   contains  no  catalyst-poisoning
heavy  metal  or  sulfur  compounds,  unburned  fuel   and   organic
emissions may perhaps  be  controlled with a  base  metal  catalyst
instead of  the  more expensive noble  metal catalysts  currently  in
use.   Methanol  also  burns   free of  carbonaceous  particulates,  a
major  emission  problem  of   diesel  engines   today.   In   short,
methanol   use   offers   the   potential   to   achieve   comparable
performance   and   engine   efficiency   as    diesel   fuel   with
significantly lower exhaust gas and particulate emissions.

     The most common methods  to  accomplish ignition  of methanol  in
a  diesel  type  engine,  so   far,   have  been  the  use  of   cetane
improving    additives    to    the    fuel,[1,2,3,4]     diesel-fuel
pilot-injection   systems,[5,6,7]   or   an   electrical   ignition
system.[8,9,10,11,12]  The use of  cetane  improvers has  resulted  in

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                                -2-

acceptable   performance  but   to   date   has   proven   otherwise
undesirable  because  of  increased  emissions,   cost,  and  safety
concerns.   Diesel-fuel  pilot-injection  systems  have  also  been
demonstrated with  acceptable  performance  and  emissions,  but  the
additional cost  and complexity of  a  second injection system  is  a
major drawback to this type of system.

     Electrical  ignition  sources have  been  used  successfully  in
several  test  projects  to  achieve  methanol   combustion   in  CI
engines.   In  a project conducted  in Brazil,[10]  glow plugs  were
used  in a small  diesel  engine  to  burn  methanol,  resulting  in
comparable  performance  and  emissions  as   diesel   fuel.    Spark
ignition  systems  have  also  been  used  successfully  to  assist
combustion of  alcohol  fuels  in standard diesel  engines as well  as
in multiple  fuel engines  such  as  the MAN-FM[11]  and White/Texaco
stratified charge engine.[12]

     Because of  the demonstrated  success  and  feasibility  of  the
test   projects  which  utilized   electrical   ignition,    OMSAPC
investigated  this  method  to  obtain  methanol  combustion   in  a
common,  domestic diesel  engine.   In addition,  three  combustion
concepts represented by the  Brazil  project and  the MAN-FM engines
were investigated.   The  combustion concepts  and test program  are
discussed next.

III. Test Program

     A.    Engine Concepts Investigated

     This  project   centered   on   the   investigation  of   three
combustion concepts  for the  use of neat methanol  in a CI engine.
These concepts were:

     1.    Glow  Plug   "Torch"   Ignition  -    This   configuration
consisted  of  the   addition  of a  glow  plug  directly  into  the
combustion chamber,  and  modification of  the  injector  nozzle  to
concentrate  the  fuel  spray  near  the glow plug.   The  glow  plug
provides  a ,source  of  ignition  as  the  concentrated   spray  is
introduced.   This   system is   based  on  the  Brazil  project  and
approximates   the   White-TCCS   lean-burn,    stratified    charge
combustion.

     2.    Spark Plug   "Torch"  Ignition  -  This configuration  is
similar to the glow plug  ignition  concept  except  a  spark is  used
to initiate  combustion.   The fuel  spray  is concentrated near  the
ignition   source,  and,  thus   also   approximates   the  White-TCCS
stratified charge combustion.

     3.    Fuel Deposition, Spark Ignition -  This  concept  is based
on the MAN-FM  process  where  fuel is deposited on  the piston bowl,
combustion is  initiated with  a spark and  sustained  by  continued
evaporation of the  fuel  into the hot  rotating  air.  The heat  for

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                               -3-

vaporization   is   theoretically  supplied   by  flame   radiation,
therefore, the  rate of mixture  formation is  proportional to  the
intensity of combustion.   This  functional segregation of  the  fuel
and air provides the stratified  charge necessary for  combustion in
an unthrottled engine.

     With these combustion concepts and  the  required  modifications
for engine optimization in mind, a set  of criteria were developed
to  select  the best   engine  possible   for  testing.    The  engine
selection is discussed  next.

     B.    Engine Selection

     This  engine  was  chosen   after  a careful  review  of   the
technical  specifications  and  design  parameters  of  all  domestic
heavy-duty  diesel  engines  certified  for   1981.   The  following
criteria were used to select the engine.

     The engine should  be/have:

     1.    A small heavy-duty engine (150-220 rated HP).

     2.    Adequate space  in  the head and  combustion  chamber  for
the addition  of a  glow  plug or  spark  plug  and  sleeve in  each
cylinder.

     3.    The capacity for  a two-fold  increase  in  fuel delivery
volume  since  methanol's  energy  density  is  roughly  half that  of
diesel fuel.

     4.    Direct fuel injected with  easily  controlled  injection
parameters  such  as timing,  opening pressure,  spray  pattern,  and
spray direction.

     5.    A high swirl, mexican hat type piston.

     6.    As  few  engine cylinders  as possible  to  lessen  the
modification effort.

     The  turbocharged  IHC DT-466B  was  one   of four  engines  which
best  met  the  above  criteria  for  selection  for  the  project.
International  Harvester  generously  agreed  to  donate  the  test
engine to the project,  and engine selection was complete.

IV.  Test Operation and Results

     A.    Diesel Baseline

     The  engine  was  first  tested,   as  received,   to  determine
baseline  performance   and emissions  levels   on  diesel  fuel  for
comparison  to operation  on  neat   methanol.   The  following  test
sequence was observed:

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                               -4-

     1.    Two fine-fuel maps - These consisted of measurements  of
output power, fuel  flow,  and air flow  over a 90 point  speed-load
matrix, i.e.,  ten power  points  from 10-100  percent  load at  each
speed increment of 200 rpm from 1,000-2,600 rpm.

     2.    Also  performed  were  13-mode   steady-state   emissions
tests.

     3.    Three   transient  emissions   tests   over   the    1984
Heavy-Duty Federal  Test  Procedure  with  two  additional  hot-start
tests were also performed.

     4.    Results  - This  engine  exhibited  emissions  and   brake
thermal efficiency  results  typical  for  its  size and class.  The
transient  emissions results  are  summarized  in  Table  1 and  an
engine efficiency map is shown in Figure 1.

     B.    Glow Plug "Torch" Ignition

     Several  modifications  were  first  performed   in   order   to
operate  the  engine  on  pure methanol  with  glow  plug  ignition.
These modifications are listed below.

     1.    A  second cylinder head  was  procured  and fitted  with
steel sleeves through the water  jacket  to hold the glow  plug  (and
spark  plugs   for   later  configurations).   Because   of   space
limitations  the  glow/spark  plug  could  only  be  placed in one
location,  near  the edge  of the piston  cup  on the   exhaust  valve
side (see Figure 2).

     2.    Several standard and also blank, unhardened nozzle  tips
were  procured  from  their— manufacturer  for machining  of  four
different spray patterns.  These consisted of:

     a.    A  set  with  a  single spray  hole  twice  the  area of  a
standard hole directed towards the ignition source;

     b.    A set with a single spray hole four times  the  area  of a
standard hole directed towards the ignition source;

     c.    A set with four  standard  size  spray holes  arranged  in a
135° quadrant directed towards the ignition source;

     d.    A  set  of  standard nozzles  with  an  extra  spray  hole
pointed directly at the ignition source.

     3.    To increase the  fuel delivery  capacity, the rotary  head
assembly on  the  injection pump  was  replaced  by  one  with  a  larger
plunger bore and zero retraction delivery valve.

     4.    A  system was  devised  to  quickly  change  the  static
injection  timing  in 11° increments  by  rotating  gear teeth  on the
main drive of the injection pump.

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                    -5-







                Table  1




Diesel Baseline Transient Test Results
Composite FTP Emissions Results
Number
3
Number
3
Number
5
HC
(g/BBP-hr)
CO
(g/BHP-hr)
NOx
(g/BHP-hr)
Fuel
(#/BHP-hr)
Particulate
(g/BHP-hr)
1.31 3.55 9.29 .49
.12 .08 .40 .02
Composite Cold-Start Emissions Results
HC CO NOx
(g/BBP-hr) (g/BHP-hr) (g/BHP-hr)
Fuel
(#/BHP-hr)
Particulate
(g/BHP-hr)
1.43 3.73 9.29 .49
.21 .17 .36 .003
Composite Hot-Start Emissions Results
HC
(g/BBP-hr)
1.36
.13
CO
(g/BHP-hr)
3.50
.09
NOx
(g/BHP-hr)
9.32
.35
Fuel
(#/BHP-hr)
.49
.02
Particulate
(g/BHP-hr)
-

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                              -6-

                        Figure 1
              Engine  Thermal  Efficiency Map
               IHC  DT-466B  Diesel  Baseline
100

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                 rigure
          Combustion  Chamber
     Glow Plug  "Torch"  Ignition
                 figure
          Conbustion  Chamber
         Spark  i:Torch':  Ignition
-7-

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                               -8-

     5.    A system  was devised  to rotate  the  injectors  so  the
spray could be  directed to any location in the combustion chamber.

     6.    Test Matrix - A test  matrix was conceived  to determine
the  optimum operating  configuration  by  varying  several  control
parameters.  The  parameter  variations and   speed  sequence  which
comprised the test matrix  are  listed in Table 2.  The  testing  was
conducted such that  nearly all possible combinations  of parameter
adjustments were  evaluated.   The  performance measure was  simply
maximum torque  at given speeds.

     When an optimum configuration was obtained,  the engine was  to
be  tested  over fine-fuel  maps,  steady-state  emissions tests  and
transient emissions  tests.   However, as  will be discussed  later,
no configuration proved to be acceptable for  emissions  testing.

     7.    Results - The performance and efficiency results of  the
best configurations  are shown in  Table 5.   The best  performance
obtained was 246 ft/lbs at 1800 rpm  and best  efficiency 28  percent
brake thermal efficiency at  1400  rpm.   The best  power  obtained  is
48 percent  and best  efficiency 84 percent of  corresponding  diesel
operation.   This  relatively poor  performance on methanol  may  be
attributed    to   several   factors.    Methanol's  high   heat   of
vaporization,  hence  long  ignition delay,  necessitated  early  fuel
injection (as much as 91°  BTDC) to achieve best  performance.   This
early injection  combined  with the  high swirl  and  typically  lean
diesel operation probably resulted in a nearly homogeneous  mixture
far  too  lean  to  sustain  complete  combustion.   Analysis  of  raw
exhaust revealed  that  large amounts (6,000  ppm) of unburned  fuel
were   present,    indicating   that   incomplete   combustion   was
occurring.   The poor results are likely indicative of  the  tradeoff
between  an  early   injection   allowing   methanol   to   become
combustible, and an early  injection  allowing  the charge to  be more
thoroughly   dissipated.   Ignition delays  probably were too  large
and  flame   propagation  too inadequate  to permit  late  injection.
Also,  the   location  of  the   ignition  source  in  the  combustion
chamber may not have been  ideal,  but could not  be changed  because
of space limitations.

     Because  of  the  poor  performance,   this  engine  combustion
concept was not subjected to fine-fuel maps and emissions tests.

     C.    Spark "Torch" Ignition

     The operation   and  optimization  of  this   engine  with  spark
assistance   required,  in  addition  to  the   modifications   listed
previously for glow plug ignition,  the following changes:

     1.    Installation of spark plugs (see Figure 3).

     2.    Mountings  were   fabricated  and   electronic  controls
assembled so two different ignition  systems could be used:   a high
energy ignition and a multiple spark discharge ignition.

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                                      -9-
                                   Table  2

              Parameters Varied  for Methanol  Glow Plug  Ignition

Sequence                                                       Static Injection
 Speed    Injection Nozzles  Nozzle Rotation  Glow Plug Depth   Timing (BTDC)
800
1,000
1,200
1,400
1,800
2,200
2,600
5-hole
1 hole, 2x area
1 hole, 4x area
quadrant



Stock
45° CCW from
stock (upswirl)
45° CW from
stock (down-
swirl)

3/4"
her,
3/8"




into cham-
5/8", 1/2",
,1/4", 1/8"

\


16°
49°
82°




,27°, 38°,
,60°, 71°,





                                    Table 3
                 Parameters Varied for Methanol Spark Ignition


Sequence
Speed
800
1,000
1,200
1,400
1,800
2,200
2,600



Injection Nozzles
5-hole
1 hole, 2x area
1 hole, 4x area
quadrant





Nozzle
Rotation
Stock
45° CCW
90° CCW
45° CCW
90° CCW
180° CCW



Spark Plug
Depth
1/4"
1/2"
9/10"
into
chamber


"^

Ignition Ignition
System Timing
High Energy, MET
Multiple
Spark




Static
Injection
Timing
(BTDC)
16°, 27°
38°, 49°
82°, 60°,




                                    Table 4
                Parameters Varied for Methanol Fuel Deposition
Sequence  Injection   Nozzle   Piston  Spark   Ignition
 Speed     Nozzles   Rotation   Type    Plug     System
           Static
          Injection
Ignition    Timing
 Timing     (BTDC)
800
1,000
1,200
1,400
1,800
Pintle
Tube



Stock
45° CCW
45° CCW


"Bowl" 1/4"
"Dam" 1/2"
9/10"


High Energy, MET
Multiple Spark,
Glow Plug


16°, 27°,
38°, 49°,
60°, 71°,
338°, 349°,
360°, 371°

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                           -10-







                        Table 5




Best Performance Configurations with Glow Plug Ignition
Speed
1000
1400
1800
2000
Torque
169
203
246
235
Brake Fuel
Horsepower (Ib/hr)
32.18
54
84
89
.11
.31
.49
37
57
139
160
.20
.41
.40
.00
Air /Fuel
Ratio
16.6
16.4
9.8
9.8
Thermal Nozzle
Efficiency Type
25.6%
28.02%
18.1%
16.6%
2x area
2x area
2x area
2x area
Rotation
Stock
Stock
Stock
Stock
Injection
Timing
60°
60°
60°
60°
BTDC
BTDC
BTDC
BTDC

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                               -11-

     3.    A  device  was  installed  to  change   ignition   timing
electronically.

     4.    Extended  electrode  spark  plugs,  specifically designed
for this project, were procured.  Three different  electrode  length
sets were  used;  one  extending  1/4"  into  the combustion chamber,
one extending 1/2"  into the  chamber  with  the  ground  electrode
parallel to the center electrode, and one extending  9/10" into  the
chamber, (see Figure 6).

     5.    Test   Matrix  -  The  optimization  test  matrix  for  the
spark  ignition configuration  was performed in the same manner  as
for glow plug ignition.   Nearly all combinations of  the  parameter
adjustments and  speed sequence listed in Table 3  were evaluated.

     6.    Results - The performance  and efficiency  results  of  the
best spark,  ignition  configurations  are shown  in  Table  6.   The
best performance obtained was 230  ft/lbs.  at  1800 rpm which  is  46
percent  of   diesel   baseline   levels,   and   best   brake   thermal
efficiency, estimated at 30 percent at  1400  rpm, is  84 percent  of
diesel baseline.

     These results were  very  similar to  those  obtained with glow
plug ignition.  The  relatively  poor performance  may  be attributed
to  the same  factors  discussed  previously for glow  plug ignition
combustion,   namely   methanol's   high   heat    of   vaporization
necessitating early  injection,  high swirl precluding  a stratified
charge at early injection timings,  and non-optimum ignition  source
placement.   Even  throttling  the   intake  air  could  not  achieve
better performance.

     D.    Fuel  Deposition

     The additional  modificatons  required  for the  Fuel Deposition
Concept testing  are listed below.

     1.    A  set of  pistons with a  bowl  shape cavity and a  lip  to
aid fuel retention was machined. (See Figure  4)

     2.    A  set  of  pistons with  two dams welded  to  form a  90°
quadrant directly  beneath  the ignition  source  for  fuel  retention
was machined. (See Figure 5)

     3.    A set of pintle nozzles was procured.

     4.    A  set  of  fuel  nozzles  with  a fuel  passage  extension
brazed onto the  tip  and  a threaded tube extending to just  beneath
the ignition source was machined. (See Figure  7)

     5.    A  set  of  spark  plugs   with  three   extended   ground
electrodes was procured and machined to fit the sleeves.

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                                                        '"'able 6
                                  Best Performance Configurations with Spark Ignition

                 Brake       Fuel    Air/Fuel   Thermal    Nozzle            Injection   Ignition
Speed  Torque  Horsepower   (Ib/nr)   Ratio    Efficiency   Type   Rotation    Ti-ming     Timing
Spark Plug
1000
1400
1800
2000
1000
1400
1800
2000
183
220
230
184
110
100
150
110
34.84
58.64
78.82 129.41
77.07
20.94 43.86
26.66 61.81
51.41 83.75
46.08 108.22
-
Est
9.4 18
-
12.3 14
12.5 12
13.6 18
13.6 12
-
. 30%
.11%
-
.16%
.81%
.24%
.65%
Quad
Quad
Quad
Quad
5-hole
5-hole
5-hole
5-hole
Stock
Stock
Stock
Stock
Stock
StOCK.
Stock
Stock
71°
71°
71°
71°
71°
71°
71°
71°
BTDC
BTDC
BTDC
BTDC
BTDC
BTDC
BTDC
BTDC
32° BTDC
32° BTDC
32° BTDC
32° BTDC
41° BTDC
35° BTDC
28° BTDC
16° BTDC
1/4"
1/4"
1/4"
1/4"
i/4"
1/4"
1/4"
1/4"
into chamber
into chamber
into chamber
into chamber
into cnamber
into chamber
into cnauioer
into caainber
                                                                                                                        NJ
                                                                                                                         I

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                 Figure 4
         Bowl Combustion Chamber
    •Fuel  Deposition - Spar!; Ignition
                Figure  5
        Dan Combustion  Chanber
   Fuel Deposition  -  Spark  Ignition
-13-

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                        -14-
                     Fi^ure  6
          Extended Electrode Spark  Plugs
1/4"


 ft]
1/2'
                     Figure 7
          Fuel  Deposition Tube Nozzles

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                               -15-

     6.    Test Matrix - The optimization test matrix for  the  fuel
deposition combustion concept was  performed  first with the  "bowl"
pistons  and  then  with  the dam  pistons.   Two   sets  of  injector
nozzles capable of  depositing  fuel on the piston cup surface  were
evaluated.   The  first  set, the  Bosch  pintle nozzles,  had  good
deposition characteristics  with  a  mid-pressure,   concentrated  fuel
stream formed by injection.  A major  drawback  to  these  nozzles was
that the  spray direction  could  not  be  varied,  and the  resulting
injection was  directly  opposite  the ignition  source   (see  Figure
4).  The  second set  of nozzles,  the machined  tube nozzles,  had
good  fuel location with  the  stream directed   just  beneath  the
ignition  source,  however  they  possessed  a  large   sac  volume
resulting in some  "dribbling"  of  the   fuel  and a  more  disperse
spray.   A combinations of these  two  nozzles  would   have  been
preferable,   although not practically possible.   Also investigated
with  this combustion  concept  was  the   injection of fuel at  the
beginning of the intake stroke.    The  parameters varied  for  the
test matrix are listed in Table 4.

     7.    Results  -  No detectable combustion was  achieved  with
any  of  the  deposition  test configurations.   The fuel  deposition
type  of  operation demonstrated   by  the   MAN  engine   was   not
achievable with  this  engine  and  the particular fuel  injection,
ignition, and  air  flow characteristics.  The major contributing
factor was probably the  inability to  present the  spark  to  a  region
of combustible vapors  above the fuel pool in  the piston.  Whether
sufficient vaporization existed to  create a combustible mixture at
any  location  in the  piston  cup  is open  for  question.   Other
contributing   factors    were:     non-optimum   fuel    injection
characteristics,   non-optimum  spark  location,  and  potentially  a
failure  to  cold-start  (a  warmed-up  engine  may   have   enhanced
combustion by providing heat for initial fuel vaporization).

V.   Summary

     1.    Combustion  of neat methanol  was  achieved in  a  common
heavy-duty diesel  engine,   an  IHC  DT-466B,  using glow plugs  and
spark plugs as ignition sources.

     2.    Three  combustion   concepts    for   operation   on   neat
methanol  were  attempted  with  this  engine:   glow plug  "torch"
ignition,  spark   "torch"   ignition,  and  fuel   deposition-spark
ignition.  For each concept, several  engine parameters  were  varied
to obtain optimum performance.

     3.    Results  for  glow  and  spark  "torch"   ignition  were
comparable.  The best  performance  obtained was 246 ft-lbs at  1800
rpm  and  best  brake thermal  efficiency  30  percent at 1400  rpm.
This  was  48  percent  (power)  and  84  percent  (efficiency)  of
corresponding diesel baseline operation.

     4.    No  combustion  was  achieved  with  the fuel  deposition
concepts.

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                               -16-

     5.    Combustion  of  neat  methanol  in  the  engine  was very
sensitive to the  engine operational  parameters,  and was  probably
inhibited  by  the  limitation  on   ignition  source  location, high
swirl in the combustion chamber, and very lean  air-fuel  mixtures.

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                               -17-

                            References

     1.    "The  Utilization   of   Alcohol  in  Light-Duty   Diesel
Engines," Ricardo  Consulting  Engineers, EPA-460/3-81-010, May  28,
1981.

     2.    "The Suitability of Different Alcohol Fuels  for  Diesel
Engines  by  Using  the Direct  Injection  Method,"  Pischinger,  F.,
Havenith,  C.,   Fourth International  Symposium  on  Alcohol  Fuels
Technology,  Brazil, 1980.

     3.    "Alcohols in Diesel Engines  -  A Review,"  Henry Adelman,
SAE Paper No. 790956.

     4.    "The  Utilization  of  Alternative  Fuels  in  a  Diesel
Engine Using Different Methods,"  E.  Holmer,  P. S. Berg,  and  B.  I.
Bertilsson,  SAE Paper No. 800544.

     5.    "Emission  Characterization  of  an  Alcohol/Diesel-Pilot
Fueled  Compression-Ignition   Engine  and  Its  Heavy-Duty  Diesel
Counterpart,"  Terry  L.  Ullman   and  Charles  T.  Hare,  Southwest
Research Institute, EPA-460/3-81-023, August  1981.

     6.    "The Utilization of Different Fuels in a  Diesel  Engine
with Two  Separate  Injection Systems,"  P.  S.  Berg, E.  Holmer,  and
B.  I.  Bertilsson,  Paper II-29,  Third  Symposium  on  Alcohol  Fuels
Technology,  May 29-31, 1979, Published by DOE in April 1980.

     7.    "Alternative  Diesel   Engine  Fuels;    An  Experimental
Investigation of Methanol, Ethanol, Methane, and Ammonia in  a D.I.
Diesel  Engine  with  Pilot   Injection,"  Klaus  Bro and  Peter  Sunn
Pedersen, SAE Paper No. 770794.

     8.    "Spark  Asssted   Diesel  for  Multi-Fuel   Capability,"
Dominyama, K. and Hashimoto, I., SAE 810072.

     9.    "Surface  Ignition   Initiated  Combustion  of  Alcohol  in
Diesel  Engines  -  A  New  Approach,"  Nagalingam,  B.,  et al.,  SAE
800262.

     10.   "Use  of   Glow-Plugs  in  Order   to  Obtain  Multiful
Capability  of  Diesel  Engines,"  Institute   Maua  de  Tecnologia,
Fourth   International   Symposium   on  Alcohol  Fuels  Technology,
Brazil, October 5-8, 1980.

     11.   "Results of MAN-FM  Diesel Engines Operating  on Straight
Alcohol  Fuels," A.   Neitz  and   F.  Chmela,   Fourth  International
Symposium on Alcohol Fuels Technology, Brazil,  October 5-8, 1980.

     12.   "Performance, Emissions,  and  Fuel  Consumption, of  the
White  L-1635 Stratified  Charge  Engine Using  Various  Fuels,"  SA
Paper No. 780641.

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