EVAP 76-3
Technical Support Report for Regulatory Action
In-House Test Program
Report No. 4
Typical Vehicle Diurnal
October, 1976
Gary M. Wilson
Thomas Rarick
Notice
Technical support reports for regulatory action do not necessarily
represent the final EPA decision on regulatory issues. They are intended
to present a technical analysis of an issue and recommendations resulting
from the assumptions and constraints of that analysis. Agency policy
considerations or data received subsequent to the date of release of
this report may alter the recommendations reached. Readers are cautioned
to seek the latest analysis from EPA before using the information contained
herein.
Standards Development and Support Branch
Emission Control Technology Division
Office of Mobile Source Air Pollution Control
Office of Air 'and Waste Management
U.S. Environmental Protection Agency
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Contents
Page
1. Introduction 1
2. Summary and Conclusions 2
3. Literature Review 4
3.1 Typical Daily Temperature Excursions 4
3.2 Length of Diurnal 5
3.3 Amount of Fuel in the Fuel Tank 13
3.4 Summary of Literature Review 14
4. Technical Discussion 17
4:1 Program Objective 19
4.2 Program Design 19
4.3 Facilities and Equipment 19
4.3.1 Facilities 1.9
4.3.2 Equipment 20
4.3.3 Test Fuel 20
4.4 Test Procedures 20
4.4.1 Temperature Excursion and Fuel
Volume Tests 20
4.4.2 Length of Diurnal .21
5. Test Results 23
5.1 Temperature Excursion and Fuel Volume
Comparison 23
5.2 Length of Diurnal 26
•6. Discussion of Test Results 30
6.1 Temperature Excursion and Fuel Volume
Comparison 30
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6.2 Length of Diurnal 30
6.3 Recommendations for Further Study. 31
7. References 33
Appendix: Test Data
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1. Introduction
A diurnal breathing loss test is defined in the Federal Register as
"fuel evaporative emissions as a result of the daily range in temperature
to which the fuel system is exposed." The word "diurnal" means "recurring
every day" or "having a daily cycle." Test procedures are generally
based upon simulating a real-life situation. In the case of diurnal
evaporative losses, this situation is simulated in the Federal Test
Procedure by artifically heating the fuel tank (and indirectly the fuel
itself) over a one hour period, such that the tank fuel undergoes a
temperature excursion from 60 to 84°F.
The main parameters of a real-life diurnal process that should be
considered in establishing a firm foundation for a simulated test
procedure are:
a. Typical daily temperature excursions and how they compare to
the present test requirements;
b. Type and amount of fuel in the fuel tank and its effect on
diurnal emissions;
c. Length of a typical diurnal.
This report researches what is presently known about these three
aspects of fuel tank diurnal losses and compares them with the current
test procedure. An evaluation of the important differences between a
real-life diurnal and a simulated test procedure is made using data
gathered from an instrumented fuel tank. This report primarily focuses
on the mechanisms involved in the evolution of hydrocarbon vapors from a
vehicle fuel tank.
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2. Summary and Conclusions
The purpose of this study was to determine if the current diurnal
evaporative emission test simulates a real-life situation. To accomplish
this, a literature search was performed to determine the temperature ex-
cursion and length of a typical diurnal. Also, the percent volume of
fuel typically found in a fuel tank was researched.
The literature search resulted in the following conclusions:
a. A typical daily temperature excursion is from 64-84°F instead
of the 60-84°F associated with the heat build currently used
in the diurnal test simulation;
b. A typical diurnal occurs over a 10 hour period of time.
Currently the diurnal test is conducted over a one hour time
period.
c. The normal fuel tank is filled to 59% capacity instead of the
40% capacity currently used in the diurnal test simulation.
Four test procedures using combinations of either a 40% tank fill
or a 60% tank fill and either a 60-84°F temperature rise or a 64-84°F
temperature rise were performed. Results of this testing showed that a
60-84°F temperature rise results in 12.6% higher emissions than a 64-
84°F temperature rise. Also, a 40% fuel fill was found to result in a
10% higher emission level than a 60% fuel fill. Tests using 60% fill and
a 64-84°F temperature rise resulted in 19% lower emissions than tests
using a 40% fill and a 60-84°F temperature rise.
The evaluation of the length of the diurnal consisted of tests with
1, 2 and 3 hour heat builds from 60 to 84°F. The difference in emission
levels measured for these tests was found to be statistically significant.
The average value for the 3 hour heat build was 34% higher than for the
one hour heat build tests and there was a definite trend of higher
emission levels for the longer tests. The evaluation of the vapor
temperatures and pressures of the fuel tank showed roughly the same
emission levels would have been measured for the three different heat
build rates, if the vapor temperatures and pressures would have been
allowed to come to equilibrium. To account for these vapors would
require extending the one hour test thirty minutes after termination of
the heat build.
Tests conducted using a test procedure based on the results of the
literature search and the test program (64-84°F heat built over one hour
period followed by a 1/2 hour soak with a 60% fuel fill) showed emission
levels only 5.9% above (instead of 19% lower without the 1/2 hour soak)
emission levels measured for tests conducted using the current procedure
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(60-84°F heat build over I hour with a 40% fuel fill). Additional test-
ing should be performed on evaporative emission controlled vehicles to
substantiate the findings of this study.
The premise established in simulating the diurnal test is that the
fuel liquid undergoes the same temperature excursion as the' ambient.
This has not been substantiated in this study and some data exists that
show the fuel temperature never reaches the lowest nor the highest daily
ambient temperature. This data should be confirmed (or refuted) by
further testing and the further evaluations should be made at that time
on the corresponding fuel vapor temperature. The vapor temperature in
this study was found to only go through a 14°F temperature excursion
when the liquid temperature experienced a 24°F excursion. Since the
evolution of hydrocarbon vapors is a function of the vapor temperature
excursion (and we have assumed a state of equilibrium), the vapor temp-
erature should also go through a "typical" temperature excursion. This
may or may not be the same as the ambient or liquid temperatures and
controlling the vapor temperature may lead to better simulation with
less variability.
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3. Literature Review
Hydrocarbon emissions occur from the fuel tank due to increasing
temperatures which cause an expansion of gases in the vapor space. The
expanding gases may pass out of the tank vapor space and go into the
surrounding atmosphere. In the case of current evaporative controlled
vehicles, the gases should pass through a charcoal canister where the
hydrocarbons will be adsorbed on the charcoal. If the gases in the
vapor space are not allowed to expand, the pressure in the fuel tank
will build up.
Based on the above discussion, it is evident that for diurnal
emissions we are primarily concerned about periods of increasing tempera-
tures. Decreasing temperatures should have no effect on hydrocarbon
emissions. This concept is generally an accepted fact by both the
motor vehicle industry and by private researchers (1) (2) (3). Thus,
the magnitude and length of the temperature excursion which begins at
the lowest temperature of the day (in the early morning) and ends with
the maximum temperature of the day (during the late afternoon) needs to
be determined in order to be able to simulate a "typical" diurnal for
the measurement of evaporative emissions.
A "typical" diurnal temperature excursion will vary from month to
month and will also depend on geographic locality. The environmental
impact of evaporative emissions will, therefore, also vary throughout
the year and from place to place. This fact must be kept in mind so
that the diurnal test is typical of times during the year and certain
localities for which the problem of evaporate emissions is most severe.
3.1 Typical Daily Temperature Excursions
According to the report on "Fuel System Evaporative Losses" (1) ,
the maximum temperature for the diurnal phase of the evaporative emission
test appears to have been based upon, or at least substantiated by, the
median smog-day temperatures in Los Angeles during 1955-56. The maximum
temperature of 85°F was reported to have been the median smog-day tempera-
ture stated in a letter from Dr. L. A. Chambers of the Los Angeles Air
Pollution Control District to Mr. 0. P. Baker of the AMA (now MVMA)
staff.*
Since, for the most part, the problem of hydrocarbon emissions is
most acute in the urban area, a typical temperature excursion should be
determined using data from major urban areas. The average minimum/maximum
temperatures for thirty-one major metropolitan areas were investigated.
These standard metropolitan statistical areas were selected from MVMA's
1973/74 report (4) and represented 37% of the registered passenger cars
in the U.S., and 37.8% of the country's population.
*No indication of minimum temperature is given in the referenced report.
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It can be seen in Table 3-1 that the Los Angeles metropolitan area
has the largest number of registered cars, while New York has the greatest
population density. The normal monthly temperatures for the.years 1941-
70 are cited in a U.S. Department of Commerce publication (5). , The
overall average minimum/maximum temperatures for the various selected
sites, weighted for both population and vehicle density, are shown month
by month in Table 3-2. The temperature range, weighted for vehicle
density, is shown graphically in Figure 3-1.
Since the most severe smog conditions probably occur during July
and August, the test procedure should try to represent the diurnal
temperature excursions seen during those months. Table 3-2 and Figure
3-1 indicate that the maximum temperatures likely to occur during July
and August are near 85°F. Therefore, the maximum temperature currently
used in the diurnal test simulation was, as stated earlier, associated
with times with the most severe air pollution problems.
The average minimum/maximum temperatures for all months and for
July and August are highlighted in Table 3-2. The data show that the
temperature excursion seen for July and August is 64°F to 84°F, and is
the same whether the data are weighted by population, by vehicle popu-
lation or unweighted.
This information is based upon monthly average temperatures for 31
cities. A more detailed analysis is available using the daily temperatures
for the months of July and August for five specific metropolitan areas
(Chicago, Denver, Detroit, Houston and Los Angeles) which reasonably
represent major air quality control regions (6). Composite'histograms
are shown in Figures 3-2, 3-3 and 3-4. Figures 3-2 and 3-3 show the
plot for the daily maximum and minimum temperatures respectively.
Figure 3-4 is the composite plot of the daily differential temperatures.
It can be seen that the results show a 63.3 to 84.3°F temperature excursion
which is very similar to the 64.0 to 84.0°F excursion for the 31 city
monthly average. A complete set of histograms for each of the five
cities showing daily maximum, minimum and differential temperatures is
exhibited in the Appendix.
Since the 5 city detailed analysis approximates the information
derived from the 31 city monthly analysis, it appears that a diurnal
temperature excursion of 64-84°F accurately describes a summer month
diurnal in a typical U.S. urban center.
3.2 Length of Diurnal
Another item of concern is that of determining when the maximum and
minimum daily temperatures occur. This will give us an insight into the
real-life "length of diurnal."
The duration of a real-life diurnal can be determined from an
investigation of local climatological data (6). Using data for the same
5 sites used in Section 3-1 (Chicago, Denver, Detroit, Houston, and Los
Angeles) an average summary of hourly temperatures for the years 1973-74
was determined and is presented in Figure 3-5.
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-6-
CITY
Los' Angeles
New York
Chicago
Philadelphia
Detroit
San Francisco
Washington, D.C.
Pittsburgh
St. Louis
Cleveland
Houston
Newark
Minneapolis
Baltimore
Dallas
Anaheim (Santa Ana)
Atlanta
Miami
Patterson
Denver
San Diego
Seattle
Cincinnati
Tampa
Milwaukee
Kansas City
San Jose
Riverside
Portland
Buffalo
Indianapolis
TOTALS
POPULATION
x 1000
. 7032
11571
6978
4817
4199
3109
2861
2401
2363
2064
1985
1856
1813
2070
1555
1420
1390
1267
1358
1227
1357
1421
1384
1012
1403
1253 •
1064
1143
1009
1349
1109
76840
%
9.15
15.06
9.08
6.27
5.46
4.05
3.72
3.12
3.08
2.69
2.58
2.42
2.36
2.69
2.02
1.85
1.81
1.65
1.77
1.60
1.77
1.85
1.80
1.32
1.83
1.63
1.38
1.49
1.31
1.76
1.44
100
NO. CARS
x 1000
3597
3398
2815
2124
1942
1510
1303
1058
1040
1015
970
894
866
842
812
778
747
742
681
679
676
669
655
600
588
586
561
683
535
522
508
34396
%
10.46
9.88
8.18
6.18
5.65
4.39
3.79
3.08
3.02
2.95
2.82
2.60
2.52
2.45
2.36
2.26
2.17
2.16
1.98
1.97
1.97
1.94
1.90
1.74
1.71
1.70
1.63
1.99
1.56
1.52
1.48
100
Table 3-1 Major Urban Areas by Population & Vehicles
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-7-
MONTH
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sept.
Oct.
Nov.
Dec.
All Moa
Comb.
Jul. &
Aug.
UNWEIGHTED
MIN MAX.
29. AS 46.08
31.34 48.87
36.88 55.31
45.56 65.28
53.09 73.19
60.50 80.40
64.44 84.46
63.45 83.61
57.92 78.66
49.39 69.91
39.87 58.18
32.15 48.72
47.01 66.05
63.95 84.04
WEIGHTED BY POPULATION
MIN. MAX.
28.45 44.29
30.18 46.78
36.10 53.67
44.91 64.06
52.78 72.44
60.63 80.05
64.97 84.18
63.82 83.24
58.17 78.04
49.48 69.20
39.87 57.20
31.38 46.98
46.73 65.01
64.39 83.71
WEIGHTED BY 8 CARS
MIN. MAX.
29.42 45.63
31.20 48.14
36.87 54.73
45.42 64.69
53.01 72.72
60.57 80.06
64.82 84.18
63.73 83.34
58.29 78.40
49.79 69.77
40.32 58.09
32.21 48.26
47.14 65.67
64.27 83.76
Table 3-2 Average Monthly Temperatures for 31 Cities
01
s
CO
V
!
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-8-
MAX
TEMP 0
MO. OF DAYS
10 20
30
40
50
I
!»*»»»
I -tnnn> •»•»«••» -fnnnnnnnt-tnnxnf
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
fll
82
33
84
85
86
87
Flfl
89
91 I <>•»•»»•»« •»#»«»•»»««•»»•»•»»•»•»
92
93
94
95
97
98
99
100
101
102
103 «
104
105
106
107
108
109 I
Min = 67°F
Max = 103°F
Mean = 84.3°F
Figure 3-2 Composite Distribution of Maximum
Daily Temperatures - 5 Cities
(July & August)
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-9-
I*
I
WIN
TEMP 0
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
NO. OF DAYS
10 20
30
40
50
I •»««•»«•»«««««
J<
T
{«««»»««*«•»*»«»«««*««•»»««»«
IIHHHHHHHHHHHHUHHKHHHHHUHHHH
I*a*tte4O«»«a«»»«»»»**»«4««#«««««
]«•»«»«#««««»•»«»»«««#««««««»«•»«««
I »«««««•<»«•»•»«•»«•««
!«»»
I ooo
Min = 45°F
Max = 78°F
Mean = 63.3°F
Figure 3-3 Composite Distribution of Minimum
Daily Temperatures - 5 Cities
(July & August)
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-10-
NO. OF DAYS
TEMP
DIFF o
1 I
2 I
3 I*
10
20
30
40
50
S I*
6 I
7
8
9
10
11 I -IKKUXXXHi- O O tHHHXXHHX> »« tHHKHJO
12 I »»***«»*»»»«»»»#«»«»»»»*»**«««»
13
15
17 I -It •»«•»»•»»•»•»«•»•»•»«•»««••»«»«
18 I »»»»»*»»*»*«*«»»»»»*»*«»»«»
19
20
21
22
23 I ««»«•»»«• »•»•&»»•»•»•»»»»•&•&»««•»*•»«
-txxnnnxnnnj «•»
25
26
27 i ««»»«•»«•»««#«
28 I
29 I »»»*»*»»»•»»
30
31
32 !»»»»«»*»»<»»»»*»»»*
33
34
35 i»»»»*»»»»»*»»»
36
Min = 3°F
Max = 45oF
Mean-20.9'F
39
40
42
43
44
45
J«««
I
I
I
I
I*
I....*... .!....*....!
....*....!....*.... I.. .......
Figure 3-4 Composite Distribution of Differential
Daily Temperatures - 5 Cities
(July & August)
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-11-
o
00
If, «
o
UJ
M
Q: '
< c
S **
«i
t-
(n
J.IT. >-i
a.
Lu
H-
C
(iJ
rsi
HH
O
0.
2 t-o—i
OI
a o
u. >-•
(/) O
a «
X Z
Figure 3-5
Typical Daily Temperature
Fluctuation - 5 Cities
The temperatures for the five cities have been standardized to a
temperature range of 25 °F (60 to 85 °F) with the minimum daily temperature
shown at 60°F, as shown below:
T . = (25) T ~ Tmin
std — ~~
+ 60
max
min
where T is the hourly temperature for a particular city. Since we are
mainly concerned with length of diurnal, this standardization has been '
done for ease of presentation in showing the time period for temperatures
within the same range. This temperature range, as shown in Figure 3-2,
shows the diurnal, or more specifically, the average daily heat rise
occurring over a time period of approximately 10 hours. An in-depth
analysis of diurnal ambient temperature profiles was reported by W. F.
Biller and others (7). The graphical results of Biller's analysis are
shown in Figure 3-6 and presents daily maximum temperatures correspond-
ing to the 10th, 50th, and 90th percentiles. These percentiles were
obtained from a cumulative distribution of daily temperatures from May
through October. Four cities were used in this analysis, and the max-
imum temperatures corresponding to the three percentile days are shown
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-12-
100
95
90
85
80
!75
• 70
i
65
60
55
50
15
90™ PERCENT1LE
100
. 95
90
85
£- 80
1U
c:
<
UJ
I 70
65
60
55
50
15
90™ PERCENT! LE
-J
i i
00 02 Ot 06 03 10 12 11 16 18 20 22
HOURS FROM MIDNIGHT (LOCAL STANDARD TIME)
00 02 04 06 08 10 12 11 16 13 20 22
HOURS FROM MIDNIGHT (LOCAL STANDARD TIKE)
CHICAGO
HOUSTON
100
95
90
85
80
I 75
5 70
tl
a
' 65
60
55
50
15
-90™ PERCENTILE
I I I
I I I I I
00 02 0!) 05 OS 10 12 J1 15 IS 20 22
HOURS FROM MIDNIGHT (LOCAL STANDARD I IKE)
LOS ANGELES
100
95
90
85
80
! ?5
\ 70
" 65
60
•55
50
15
j i
i i i i
00 02 01 05 03 30 12 21 1C IS 20 22
HCURS FROM KIBI.'IGIlT (LOCAL STAIifiARB TIME)
YORK
Figure 3-6 Diurnal Temperature Patterns,
May-October, inclusive.
(Reprinted from ReC. 6)
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-13-
City
Chicago
Houston
Los Angeles
New York
10th
59.0
80.0
68.5
62.3
50th
78.0
89.3
82.0
78.2
90th
90.0
94.5
93.5
90.0
Table 3-3 Maximum Temperatures Corresponding to
10th, 50th & 90th Percentile Days
in Table 3-3. It is interesting to note that the average maximum temper-
ature for the four cities (50th percentile) is 81.88°F, while the average
maximum temperature for the same period (May through October) for the
31 cities used in this report (Table 3-2), is 79.60°F. In either case,
when we compare the graphical illustrations of both data, the natural
diurnal heat build time is approximately 10 hours.
On the average, the diurnal heat rise starts around 5:00 AM and
peaks at approximately 3:00 PM. Therefore, we know that the typical
vehicle is likely to have been in operation during the diurnal heat
rise. If we accept the premise that fuel tank emissions occur anytime
the fuel tank liquid temperature increases, then we can conclude that
such emissions will occcur whether the vehicle is parked or in operation.
This conclusion is in agreement with Biller's assumption in Appendix B
of his report (7).
3.3 Amount of Fuel in the Fuel Tank
As was previously mentioned, fuel tank losses are a result of
thermal expansion. As Ellsworth (8) points out, "when vapor space and
temperature decrease, the amount of fuel evaporated decreases." Thus,
it can be said that the amount of fuel in the tank (remaining from
overnight parking) directly influences the evaporative losses during the
daily heat rise. Simulation of a diurnal test, therefore, must establish
a repeatable volume of gasoline as part of the test requirements.
Presently, the Federal Test Procedures require the fuel tank to be
filled to a capacity of 40% of the nominal fuel tank volume rounded off
to the nearest whole gallon. Rounding to the nearest whole gallon implies
a tolerance of + 0.5 gallons. It also introduces an error in establish-
ing the typical fuel fill volume. The effect of this is probably minimal.
However, with presently available equipment, it is easy enough to control
the tank fill to the nearest tenth of a gallon. It is recommended that
the tank fill volume be determined to the nearest tenth of a gallon to
achieve greater consistency.
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-14-
The results of a 1969 six city survey (9) reported overnight fuel
tank readings, as shown in Table 3-4, averaged 59% full for weekday
parking, and 55% full for weekend parking. These data are shown graph-
ically in Figure 3-7 as a cumulative frequency distribution plot.
3.4 Summary of Literature Review
In summary, the typical diurnal experienced by a vehicle consists
of the following:
a. Average temperature excursion for the months of July and
August is 64 to 84PF;
b. The daily heat rise, on the average, for the months of
July and August, cover a 10 hour period of time from 5:00
AM to 3:00 PM, local standard time:
c. The average fuel tank is filled to 59% of capacity.
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Weekday
Weekend
READING
Empty
1/4
1/2
3/4
Full
Total
Empty
to
1/4
1/2
3/4
Full
Total
NYC
N %
23 2.1
215 20.2
274 25.7
301 28.3
252 23.7
1065
89 28.3
83 26.3
70 22.2
73 23.2
315
TWC
N %
25 4.7
135 25.2
157 29.3
114 21.3
105 19.5
536
58 32.9
53 30.1
36 20.5
29 16.5
176
CHI
N %
24 3.1
177 22.9
215 27.9
174 22.6
181 23.5
771
62 23.5
61 23.1
72 27.3
69 26.1
264
CIN
N %
27 4.5
150 25.3
180 30.3
133 22.4
104 17.5
594
72 32.9
58 26.5
37 16.9
52 23.7
219
HOU
N %
29 0.3
103 22.4
105 22.8
106 23.0
117 25.5
460
50 27.2
59 32.1
42 22.8
33 17.9
184
LA
N %
66 8.3
181 22.9
202 25.5
162 20.4
181 22.9
792
82 32.8
82 32.8
53 21.2
33 13.2
250
SIX CITY
N %
194 4.6
961 22.8
1133 26.9
990 23.5
940 22.2
4218
413 29.4
396 28.1
310 22.0
289 20.5
1408
Table 3-4 Overnight Fuel Tank Readings
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-16-
100
o
a,
10
a)
04
en
^ >,
o ts
C Tl
0) ^J
3 0)
cr a)
QJ g
•H
4J
tfl
rH
§
O
80
60
40
20
50% Participants
59Z
Full
I
1/8 1/4 3/8 1/2 5/8
Fuel Tank Reading
3/4
7/8
Figure 3-7 Cumulative Frequency Diagram of
Fuel Tank Readings from Six City Survey
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-17-
4. Technical Discussion
Based on the information obtained from the literature search, the
diurnal test, in order to simulate an average real-life diurnal, would
have to be run for a period of 10 hours over a 64-84°F temperature range
with the fuel tank filled to 60% capacity. The temperature excursion
(64 to 84°F) and filling the fuel tank to 60% capacity do not present
any practical problems. A 10 hour test on the other hand is excessively
long, would be vastly more expensive than a shorter test, and would put
a much heavier burden on testing facilities.
The diurnal evaporative emission test procedure currently accepted
for enclosure measurements is based upon the test procedure described in
J171a of the SAE Handbook (10). This test specifies the following:
a. Temperature excursion is 60 to 84°F.
b. The fuel tank is filled to 40% capacity.
c. Heat rise is conducted over a one hour period.
There are definite differences in the test procedure recommended by
SAE and the test procedure which resulted from the literature search.
A temperature excursion of 60-84°F would be expected to result in higher
emission levels than a 64-84°F excursion because a greater expansion of
gases in the vapor space should occur. A 40% fuel fill would be expected
to result in higher emissions than a 60% fill due to the greater vapor
volume with the 40% fill. These expected differences should be explored
in order to determine the magnitude of the actual effect. Regardless of
the magnitude of the effect, the more representative values for the test
are a 64-84°F temperature excursion and a 60% fuel fill.
The SAE procedure stipulates that the test should be performed over
a one hour period. Considering the premise that emission levels are only
a function of the expansion of gases in the vapor space, then the length
of the test shouldn't matter. This may only be true up to a point. If
the fuel is heated too quickly, it may result in an unrepresentative
test due to a pressure build-up in the tank, because gases cannot pass
out of the tank quickly enough. The fuel tank and control system design
will affect tank pressure build-up.
During a real-life diurnal, it might be assumed that the fuel
liquid and vapor temperatures undergo the same temperature excursion
(64-84°F) as the ambient. However, data from a study conducted by Scott
Research Laboratories (11) indicate that the liquid temperature lags the
ambient temperature (by approximately 2 hours) and never reaches the
same maximum or minimum value. In the data presented by Scott the
ambient temperature went from 61.0 to 87.1°F, whereas the fuel tempera-
ture saw a change of 63.9 to 84.0°F. This information (with a standard
deviation of values in each time point ranged from 3.4 to 9.8) was the
mean value developed for an 80-car fleet undergoing a 24-hour soak
period.
-------
-18-
This study did not attempt to evaluate the relationship of fuel
temperature versus ambient temperature, but rather assumed, as pre-
viously stated, that the fuel temperature was in a state of equilibrium
with the ambient and experienced the same total excursion.
During the present evaporative emission certification test and the
SAE procedure, the temperature excursion is controlled from the mid-
volume of the liquid fuel. The length of the test and the temperature
of the fuel tank prior to the start of the test may limit the temperature
excursions of the fuel vapor. It is not yet known whether, in an actual
diurnal, the liquid and vapor temperatures are in equilibrium. If an
equilibrium process is the case, and since the temperature excursion of
the vapor causes the vapor expulsion, the test should be long enough to
allow equilibrium to occur. This may require a test longer than one
hour.
4.1 Program Objective
The purpose of this study was to examine the differences in emissions
when the vehicle underwent various diurnal conditions and to determine
if significantly different emission levels exist.
4.2 Program Design
To determine the significant effects of the different procedures,
it was decided to study the mechanisms by which the hydrocarbon vapors
were generated rather than determine the effects on an actual vehicle
control system.
Therefore, an instrumented fuel tank was prepared without any vapor
control system. The fuel tank was vented into a sealed enclosure where
the hydrocarbon concentration was continuously monitored. This made it
possible to evaluate the effects of different temperature excursions,
two fuel levels, and various heat-build times.
The temperature excursions evaluated were 60-84°F based upon the
SAE J171a recommended practice (1) and 64-84°F as determined from the
literature survey. Two fuel levels were examined for their effect on
the generation of hydrocarbon losses. A 40% fuel fill was used based on
the SAE recommended practice, and a 60% fill was used based on the
literature survey. Three heat-build times of 1, 2, and 3 hours were
conducted to evaluate the effect of test length.
4.3 Facilities and Equipment
4.3.1 Facilities
The LDV Evaporative Enclosure as shown in Figures 4-1 and 4-2 was
used for all tests. The enclosure is nominally 8 feet high x 10 feet
wide x 20 feet long, and has a measured volume of 1540 cubic feet.
Calibration of the enclosure with a propane injection and recovery test
compared within + 2 percent. Propane retention tests of 2 and 4 hours
were performed periodically and indicated a leakage rate of less than
0.1 g/hr.
-------
-19-
Figure 4-1 Evaporative Enclosure (front view)
Figure 4-2 Evaporative Enclosure (rear view).
-------
-20-
4.3.2 Equipment
A 1974 Chevrolet Impala fuel tank with a nominal capacity of 22
gallons was instrumented with pressure gauges and thermocouples (see
Figure 4-3) to provide the following information:
a. Fuel liquid temperature;
b. Fuel vapor temperature and pressure;
c. Tank skin temperature.
4.3.3. Test Fuel
Indolene Type HO (8.7 - 9.2 psi RVP) test fuel was used throughout
the program.
4.4 Test Procedures
All diurnal comparative tests were conducted in the evaporative
enclosure using the instrumented fuel tank. Fresh fuel was used for
each test. The fuel was delivered from a fuel conditioning cart into
the tank at a temperature of approximately 50°F and allowed to naturally
heat to the appropriate starting temperature. A 2000 watt heat blanket.
was attached to the bottom of the tank and provided the heat for all
diurnal tests. The fuel was heated at a linear rate over the specified
period of time.
4.4.1 Temperature Excursion and Fuel Volume Tests
To determine the significance of the daily temperature excursion
(60-84°F versus 64-84°F) and the significance of the amount of fuel in
the fuel tank (40% fill versus 60% fill), a minimum of four replicate
tests of the following four test procedures were conducted:
a. 60 min., 60-84°F heat-build with 40% fill;
b. 60 min., 64-84°F heat-build with 40% fill;
c. 60 min., 60-84°F heat-build with 60% fill;
d. 60 min., 64-84°F heat-build with 60% fill.
Performing the testing in this manner allowed for comparative
evaluations of one variable at a time. In addition, the fuel tank was
allowed to remain in the enclosure for one hour after the heat was
turned off in order to determine at what point emissions cease when the
temperature rise stops. Vapor temperatures were monitored to determine
-------
-21-
Temperature
Recorder
Temperature
Controller
9
Magnehelic
,Pressure
Gauge
Tank vented
to atmosphere
Thermocouple at
70% Fill Point
/ / /•/ ////
-------
-22-
0)
M
3
4-1
cfl
M
0)
a
3
•u
•rl
3
cr
•H
h4
84 -
80
76 H
72
68 -j
64
60
0
64-84°F
Heat Build
60-84°F Heat Build
20 40
Time, min.
Figure 4-4 Heat Build Rates for
Analysis of Temperature Excursions
60
O>
M
4-1
tfl
(-1
a)
I-
0)
H
0)
•H
3
cr
68
64
60
3 Hour Heat Build
2 Hour Heat Build
1 Hour Heat Build
Time, hours
Figure 4-5 Heat Build Rates for
Analysis of Length of Diurnal
-------
-23-
5. Test Results
A total of 27 diurnal tests were conducted using the instrumented
fuel tank. The individual test results are given in the Appendix.
5.1 Temperature Excursion and Fuel Volume Comparison
Figure 5-1 shows the liquid and vapor fuel temperatures for the
four different test procedures used to analyze the effect of both the
temperature excursion and the percent fuel fill. The graphs shown in
Figure 5-1 indicate that the programmed temperature excursions were
maintained reasonably well for the actual tests. The curves also show
that liquid temperatures continued to increase slightly after the ter-
mination of the 60 minute heat build. Vapor temperatures continued to
increase until roughly 70 to 80 minutes into the test. Thus, hydrocarbon
emissions would be expected to continue to increase somewhat after the
termination of the heat build.
Hydrocarbon emissions for a 60 to 84°F temperature rise were 8.3%
higher for a 40% fuel fill and 17% higher for a 60% fuel fill than
corresponding tests for a 64 to 84°F temperature rise. Thus, tests with
a 60 to 84°F resulted in 12.6% higher emissions on the average than
tests with a 64 to 84°F temperature rise. Figures 5-2 and 5-3 graphically
show the differences between the two temperature excursions for tests
with a 40% and a 60% fill respectively.
Hydrocarbon emissions for a 40% fuel fill were 5.8% higher for a 60
to 84°F temperature rise and 14.3% higher for a 64 to 84°F. temperature
rise than a 60% fuel fill. Thus, tests with a 40% fuel fill would be
expected to result in 10% higher emissions on the average than tests
with a 60% fuel fill. Figures 5-4 and 5-5 graphically show the dif-
ferences between tests with the two fuel fills for temperature excursions
of 60 to 84°F and 64 to 84°F respectively.
In order to investigate the data to determine if these differences
are "statistically" significant, the following hypotheses will be tested:
H = Hydrocarbon loss for a 60-84°F temperature
excursion is equal to the hydrocarbon loss
for a 64-84°F temperature excursion.
x
H „ = Hydrocarbon loss with a 40% tank fill is equal
to the hydrocarbon loss with a 60% tank
fill.
Rejection or non-rejection of the above hypotheses will be based on
a t-test evaluation. Table 5-1 is a summary of this evaluation.
-------
TJ
H-
TO
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n> ja
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(T)
VJ
CU
a
co
H
o
a
n)
84 -
85 n
80 -
75 -
70 -
65 -
60
0
Fuel Temperature vs. Time
with 40% Fuel Fill
60-84°F Heat
Build
64-84°F Heat Build
20 40 60 80 100 120
Time, min.
Vapor Temperature vs. Time
with 40% Fuel Fill
..~Z 60-84°F Heat Build
64-84°F Heat Build
CU
M
4-1
rt
1-1
cu
0)
84-
80 -
76 -
72
68
cr 64 -
*ri
60
85 i
Fuel Temperature vs. Time
with 60% Fuel Fill
64-84°F Heat Build
60-84°F Heat Build
20 40 60 80
Time, min.
100 120
Vapor Temperature vs. Time
with 60% Fuel Fill
20
64-84°F Heat Build
60-84°F Heat Build
40 60 80 100 120 0 20 40 60 80 100 120
Time, min. - Time, min.
*Dotted lines indicate that data between 60 and 120 min. readings were unavailable.
i
to
-------
1
to
M
60
s 30
O
G
O
ja
o
O
20
10 -
Figure 5-2
Hydrocarbon Loss vs. Time
with 40% Tank Fill
60-84°F
Heat Build
64-84°F
Heat Build
20 40 60 80 100
Time , min .
120
CO
o
.J
CO
o
o
40 -
30 H
20 H
Figure 5-3
Hydrocarbon Loss vs. Time
with 60% Tank Fill
60-84°F
Heat Build
64-84°F
Heat Build
20 40 60 80 100 120
Time,
to
00
o
hJ
c
o
Cd
o
o
VJ
•o
>*
33
40 -
30 .
20 -
10 -
Figure 5-4
Hydrocarbon Loss vs. Time
for 60-84 °F Heat Build
40%
Tank Fill.
60%
Tank Fill
20 40 60 80
Time, min.
100 120
co
2 40
t>o
CO
S 30
C
o
,0
t-l
CO
o
o
(-1
20 '
10-
Figure 5-5
Hydrocarbon Loss vs . Time
for 64-84 °F Heat Build
40%
Tank Fill
60%
Tank Fill
20 40 60 80
Time, min.
100 120
^Dotted lines indicate that data between 60 and 120 min. readings were unavailable.
-------
-26-
Test
60-84°F vs.
64-84°F heat-
build at 40%
fill
60-84°F
64-84°F heat-
build at 60%
fill
40% vs. 60%
fill with
60-84°F heat-
build
Degrees "t"
Freedom Calculated
9 .94
6 1.42
7 .55
40% vs. 60% 8 1.46
fill with
64-84°F heat-build
"t" - Table
ex =0.20 Hypothesis
.88 Reject HQA
80% C.L.
.906 Reject H at 80%
C.L.
.896 Cannot reject
HOB
.889 Reject H at
80% C.L?B
Table 5-1. T-Test Evaluation of Temperature
Excursion and Fuel Volume.
Table 5-1 shows that with either a 60% or a 40% tank fill, the
test data indicated that (at 80% confidence) the 60-84°F heat-build
produced higher emission levels than a 64-84°F heat-build. The Table
also shows that (at 80% confidence) the tests with a 60% tank fill
resulted in lower emissions than with a 40% tank fill with a heat-build
of 64-84°F. The data for 60-84°F heat-builds did not support rejecting
the hypothesis at a 80% confidence level, but the trend was similar.
5.2 Length of the Diurnal
The liquid and vapor temperature excursion for the one, two and
three hour heat build times are shown in Figures 5-6 and 5-7 respec-
tively. Figure 5-6 indicates that the liquid fuel went through pro-
grammed heat builds reasonably well.
Figure 5-7 shows that the initial vapor temperatures were roughly
the same for the three heat build times. It should be noted that the
initial vapor temperatures were nearly 8°F higher than the initial
liquid fuel temperatures. The final vapor temperatures were slightly
higher for longer heat build times (1.7°F higher for the 3 hour test
compared with the one hour test) due to the additional time for heat
transfer from the liquid to the vapor. The final temperatures were
still 1 - 2°F lower than the 84°F final temperature of the liquid fuel.
The overall temperature excursion in the vapor space was about 14°F
compared to the 24°F rise (60-84°F) of the liquid fuel.
-------
-27-
88 i
84
« 80
3
2 76
-------
-28-
Figure 5-8 shows the tank pressure changes for the three heat build
rates. The one hour heat build showed much more erratic pressure changes
than the 2 or 3 hour tests and the pressures were increasingly higher
for the shorter test times.
Figure 5-9 shows the hydrocarbon loss versus time plots for the
three heat-build times. The figure also indicates the range of data at
the end of the heat build for the three tests. On the average, the two
hour heat build resulted in 10.5% higher emissions than a one hour heat
build, and the three hour heat build resulted in 34% higher emission
than a one hour heat-build.
The test data for the effect of the length of the diurnal test (1
hour vs. 2 hours vs. 3 hours) must also be statistically analyzed. A one
dimensional analysis of variance test can be applied to the test data
for the three test lengths to test the following hypothesis:
H : Hydrocarbon emission for a one hour heat-build (60-84°F with a
40% tank fill) are equal to emissions from a two hour test and
equal to emissions from a three hour test.
Table 5-2 summarizes this evaluation.
Mean
Sum of Degrees Mean Square F at a 95%
Squares of Freedom Square Ratio Confidence Level
Test Length 137.90 2 68.95 6.31 4.26
Residual 98.26 9 10.92
Total 236.16 11 21.47
Table 5-2. Analysis of Variance for 3 Different Test Lengths.
On the basis of the above analysis, it can be concluded with 95%
confidence that a significant difference in emissions occurs for the
three heat-builds.
-------
-29-
0)
3
CO
Q) O
£ IT
^ CO
H O
c
tH -H
0)
C/
0)
4J
C
.25 -,
,20 -
.15 -
.10 -
,05 -
1 Hour Heat Build
3 Hour Heat Build
2 Hour Heat Build
1 2
Time, Hours
Figure 5—8 Tank Pressure vs. Time for
1, 2 and 3 Hour Heat Builds
co
§
VJ
oc
CO
CO
O
c
O
CO
a
j-i
•X3
40
35
30-
25 -
20
15 •
10 -
5 -
(1)
3 Hour Heat Build
2 Hour Heat Build
1 Hour Heat Build
No data for dashed lines
except termination point
one hour after heat build
Time, Hours
Figure 5-9 Hydrocarbon' Loss vs. Time
for 1, 2 and 3 Hour Heat Builds
-------
-30-
6. Discussion of Test Results
6.1 Temperature Excursion and Fuel Volume Comparison
The current recommended practice of a 60-84°F temperature excursion
and a 40% fuel fill were not found to accurately represent a "typical"
diurnal. Tests using a 64-84°F temperature rise and a 60% fuel fill
resulted in 19% lower emission levels than tests with the recommended
60-84°F and 40% fuel fill. Emission levels were 6% higher for the 64-84°F
temperature rise and 60% fuel fill when HC were measured 1/2 hour after
the end of the heat build. The use of these values supported by the
literature search should not impact the practicality of the test and
should be very easy to implement.
6.2 Length of the Diurnal
The testing performed to evaluate the effect of the length of the
test on diurnal emissions consisted of tests of either 1, 2 or 3 hours
duration. Although it was determined that a "typical" diurnal occurs
over a 10 hour period, it was felt that the 1, 2 and 3 hour tests would
be sufficient to establish any important trends. Also, a 10 hour test is
much too long to be practical as it would be an excessive burden on test
facilities.
The differences in emission levels for the three test lengths were
found to be statistically significant, and there did exist a trend of
increasing emissions with test length that showed sizable differences
between the one and three hour results. This fact does not agree well
with the presumption that emissions only depend on the temperature rise
and not on time.
Wade (3) presents a theoretical equation for predicting diurnal
losses. His equation shows that diurnal emissions are a function of the
vapor temperature, the vapor pressure of the fuel, the tank pressure,
and the vapor space. The tank pressure during the one hour diurnal was
shown to increase by 0.2 inches of water, whereas during the 3 hour
diurnal there was no increase. A 0.2 inch of water difference is very
small, however, compared to a 33 feet of water total pressure of the
tank. Also, the volume of the vapor space would not have significantly
affected the results of the 1, 2 or 3 hour diurnal tests. Therefore,
the vapor temperature is the parameter which would affect diurnal emissions
the most.
If one assumes that the fuel and vapor are in equilibrium, the Wade
equation would predict that the 3 hour diurnal tests would have had 16%
higher emission levels than the one hour test (based on the measured
vapor temperatures). There exists a discrepancy between this value and
the observed 25% difference. The assumption that the diurnal heat build
is an equilibrium process in the way the test is conducted could be
responsible for the discrepancy. The three hour heat build would be
-------
-31-
expected to be closer to an equilibrium process than the one hour heat
build. If this is the case, the difference between a one and three hour
diurnal would be expected to be as shown, larger than 16%. Without
actual data, however, quantification of the degree of equilibrium of the
two heat build rates is not possible.
The emission level measured one hour after the end of the one hour
heat build was approximately (within 6%) the same as at the end of the
three hour heat build. The vapor temperature also increased slightly
during the hour following the one hour heat build so that the vapor
temperature rise was roughly the same as for the three hour heat build
test. This fact implies that liquid-vapor equilibrium was not totally
accomplished during the one hour heat build. If it were, the emissions
after the second hour probably would not have increased, and not been as
large as for the three-hour test. Thus, the primary problem appears to
be the lack of temperature equilibium for the shorter heat build times.
Vapor temperature profiles presented in Figure 5-1 for tests evalu-
ating the effect of the temperature excursion and the fuel fill also
showed that vapor temperatures continued to increase during a 10 to 20
minute period following the end of the heat build (as mentioned above).
If measurements were continued for 1/2 hour after the end of the heat
build the emission levels for a one, two and three hour test would
probably have been nearly the same. Thus, a short test (one hour) may
be able to simulate a 10 hour diurnal, if the test is extended slightly
to allow the vapor temperature to stabilize. This of course tends to
indicate a need to control the vapor temperature rise rather than the
liquid temperature rise.
6.3 Recommendations for Further Study
The above discussion indicates that a diurnal test procedure utilizing
a 60% tank fill and consisting of a one hour, 64 to 84°F heat build fol-
lowed by a 1/2 hour soak would adequately simulate a "typical" vehicle
diurnal. Since emission measurements were continued for an additional
hour after the heat build termination, a direct comparison between the
SAE test parameters, [40%, 60-84°F, 1 hr.], and the parameters developed
as a result of this study, [60%, 64-84°F, 11/2 hrs] can be made. The
SAE procedure resulted in an average of 24.8 g/test (Appendix Table 4-
C); whereas, the average emission level from the developed procedure
[60%, 64-84°F, 1 1/2 hr.] was 26.2 g/test (Appendix Table 1-C). Thus,
even though the measurement period of the developed procedure was increased
1/2 hour beyond the heat build, the decrease in vapor volume and tempera-
ture excursion limited the increase to only 5.6% over the SAE recommended
practice. Although a change from the SAE method to the developed procedure
may result in a better simulation of a typical diurnal, the resulting
level of emissions may not be significantly different.
It is recommended that further tests of one, two and three hour
heat build times on controlled vehicles be performed and that temperature
and emission data be gathered beyond the end of the one and two hour
-------
-32-
heat builds. Should such a study confirm that the difference in emission
levels is less than 6% between the developed procedure and the SAE
recommended procedure, then a change in the currently recommended pro-
cedure would only lengthen the test and would therefore be undesirable.
Another area of concern which was brought out by the test data is
the difference between the temperature rise of the vapor space and the
temperature rise of the liquid fuel; It was found that while the liquid
fuel underwent a 24°F temperature rise, the vapor space only saw a 14°F
temperature rise. The initial temperature of the tank was several
degrees higher than the 60°F initial temperature for the heat builds.
Since the premise is that emissions are a result of gas expansion brought
about by an increasing vapor temperature, a possibility exists that
controlling the temperature excursion of the vapor space will provide a
more representative simulation of the real-life condition and bring
about a better equilibrium process. Further investigation in this area
is warranted, not only in providing a more accurate test, but also in
the practicality of performing such a test.
-------
-33-
7. References
1. "Fuel System Evaporative Losses," Induction System Task Group
of the Vehicle Products Combustion Committee, September, 1961,
issued by Automotible Manufacturers Association AMA Engineering
Notes 616.
2. D. J. Patterson and N. H. Henein, "Emissions from Combustion
Engines and Their Control," Ann Arbor Science Publishers,
Inc., Ann Arbor, 1972.
3. D. T. Wade, "Factors Influencing Vehicle Evaporative Emissions,"
SAE Paper No. 670126.
4. "1973/74 Automobile Facts and Figures," Motor Vehicle Manufac-
turers Association of the United States, Inc., Detroit,
Michigan.
5. Climatograph of the United States No. 84, "Daily Normals of
Temperature and Heating and Cooling Degree Days 1941-70," U.S.
Department of Commerce, September 1973.
6. "Local Climatological Data," U.S. Department .of Commerce,
National Oceanic and Atmospheric Administration.
7. W. F. Biller, M. Manoff, J. Sachdev, W.C. Zegal, D. T. Wade,
"Mathematical Expressions Relating Evaporative Emissions from
Motor Vehicles without Evaporative Loss-Control Devices to
Gasoline Volatility," SAE Paper No. 720700.
8. E. Ellsworth, "Assessment of Light Duty Vehicle Evaporative
Emission Control Technology." EPA-MSAPC In-House Report. No.
EVAP 75-3.
9. R. L. Kearin, D. H. Lamoreaux, B. G. Goodwin, "A Survey of
Average Driving Patterns in Six Urban Areas of the United
States," System Development Corporation, TM (L) Y119/007/00,
January 1971.
10. "Measurement of Fuel Evaporative Emissions from Gasoline
Powered Passenger Cars and Light Trucks using the Enclosure
Technique," SAE Recommended Practice, SAE J171a, SAE Handbooks.
11. "Time-Temperature Histories of Specified Fuel Systems, Volume
I", Coordinating Research Council, Cape-5-68, October, 1969.
-------
Appendix
-------
A-l
MAX
TEMP 0
I
65 .1
66 I
67 I
68 I
69 I
70
71 I*
72 I»
73 I»
NO. OF DAYS
10 20
30
^0
50
75 !»*»
77
78
79
80
81
8?
83
84
85
8f>
87
88
89
90
91
93
93
9^»
95
96
V 97
98
99
100
101
102
103
104
105
^06
107
108
109
« ««*•»•«• •»
J»«»»
I
I*
I
I
I
I
Min.— 67°F
Max- = 97°F
Mean = 82.6°F
Chicago, Illinois O'Hare Int. Airport
Elevation 658 ft.
Figure 1 Distribution of Max. Daily
Temp. - Chicago
-------
A-2
MO. OF DAYS
MIN
TEMP 0 10 20 30 40 50
I*«** + >***I**«**'««**I***«'*>*»»I**«*'f«*««T**** + «««»T
45 I
46 I
47 I
48 I
49 I
50 I
51 I**
52 I
53 !»«»
54 I
55 !•»***
56 I*»
57
58
59 j
60 i
61 i
62 I
63 {
64
65 !»»*»
66 I*
67 I
68
69
70
71 I«»*
72 I ***»«•*
73 !»»«
75
76 I
77 I
78 I
79 I
80 I
81 I Min. = 51°F
8? I Max. = 75°F
83 I Mean = 63.8°F
84 I
85 I Chicago,, Illinois O'Hare Int. Airport
86 I Elevation 658 ft.
87 I
88 I
89 I
Figure 2 Distribution of Min. Daily
Temp. - Chicago
-------
A-3
NO.. OF DAYS
TEMP
OIFF 0 10 20 30 ^0 50
I««*»+****I*«*«+***>I>**«***«*I«»*«**««»T««««+»».*I
1 I
2 I
3 I*
41*
5 I*
6 I
7 I**
8 I»*
9 1**
10 I •***
11 I«
1? I**
If— JL
13 i««««
* ^ ^
15 i»»*»»»<»
16 j**«*«
I^Jvwwwwwv-w
13 j•»»»»«««»»««««
19
20
21
22
23
24
25
26
27
2B
29
30 I
31 I
32 I»«
33 I
34 I
35 I
36 I Min. = 3°F
37 I Max. = 32°F
38 I Mean = 18.8°F
39 I
^0 I Chicago, Illinois O'Hare Int. Airport
41 I Elevation 658 ft.
4? I
43 I
44 I
45 I
Figure 3 Distribution of Daily
Diff. Temp. - Chicago
-------
A-4
NO. OF DAYS
MAX
TEMP 0 10 20 30 40 50
I»*»* + .**«I**.*'*'***«I**«*'*****I*.«.+ ••••!••* • + ••••!
65 I
66 I
67 I*
68 I
69 I
70 I*
71 I
72 I
73 I*
74 I
75 I**
76 I*
77 I*
78 I*«
79 I**
80
81
82
83
84
85
86 I
87 I-
88 !»*#
39 j »•»«• -tut-tn*
90
91
92 I
93 I
94 I •»•»*••»•»««•»•»*•
95 i •»«•»•»«•
96 I»
97 1»
98 I
99 I»
100 I*
101 I
102 I
103 I*
104 I
105 I
Min. = 67°F
Max. = 103°F
j06 i Mean = 87.8°F
107 I
108 I Denver, Colorado Stapleton Int. Airport
109 j Elevation 5283 ft.
Figure 4 Distribution of Max. Daily
Temp. - Denver
-------
A-5
NO. OF DAYS
TEMP 0
10
30
30
40
50
I»*
46
t7
48
49
50
51
52
53
54
55
56
57
5g
59
60
61
62
63
64 I
65 I
66 I
67 I
68 I
69 'I
70 I
71 I
72 I
73 I
74 I
75 I
76 I
77 I
78 I
79 I
30 I
81 i
B2 I
83 I
84 j
85 i
86 I
87 I
88 I
89 I
I*»
I *«»*«•«•***
I •»«••»•»•»•»
I ** »•»»» <* •»»•»
Min. = 45°F
Max. = 67°F
Mean = 56.6°F
Denver, Colorado Stapleton Int. Airport
Elevation 5283 Ft.
Figure 5 Distribution of Min. Daily
Temp. - Denver
-------
A-6
MO. OF DAYS
TEMP
DIFF 0 10 20 30 40 50
II*
21
3 I
41
5 I
71
81
91
10 I
11 I
12 I
131
14 I .
15 I
16 I
17 I
18 I
19 I
20
21
22
23
24
25
26
27
28
29
30
32
34 i»*»**»* Min. = 15°F
,3 I> JwiHrViHHHHHHrww M3.X • = ^5 F
35 i»»»#«*#* Mean = 31.1°F
*^ "> T jt. x
37 I»*
38 I»* Denver, Colorado Stapleton Int. Airport
39 !<»** Elevation 5283 Ft.
40 I
41
42 I
43 I
44 I
45 I'
Figure 6 Distribution of Daily
Diff. Temp. - Denver
-------
A-7
NO. OF DAYS
MAX
TEMP 0 10 20 30 40 50
I««*« + *«**I****^*«*«1**«*'***«*I**«*^'««*«I»**« + **«*I
65 I .
66 I
67 I
68 I
69 I*
70 I
71 I
73 I»»
74 I«
75 I»
76 I***
77 I»
79 j «•«•»•» «•
79 j «••»«••»
30 {«««««•»«»««
P. I i o-H-•»•» •»•»•«•
82
83
84
P5 I 4 « <* ft tt O «• «• •» «
86 I»»»«"»«•
fi7 j»«««««»»
88 !«•«*•<»•»•&•»
89
90
91
92
93 I*
94 I»
95 I*
96 I«
97 I*
98 I
99 I
100 I Mln. = 69°F
1011 Max. = 97°F
102 I Mean = 83.6°F
103 I
104 I Detroit, Michigan Metropolitan Airport
105 I Elevation 633 ft.
106 I
107 I
108 I
109 I
Figure 7 Distribution of Max. Daily
Temp. - Detroit '
-------
A-8
NO. OF DAYS
MIN
TEMP 0 10 20 30 40 50
I«««*+*«**I»«**+>«*»I>*«***«»*I*«*»****.I«*»»+*.»«I
45 I
46 I
47 I
48 I
49 I»
50
51
52
53 !**«
54 I
55 !»»»**»»*»*
56 I**
57
58
59
60
63
65
66
57 j•»««••&•»•»
68
69
70 I»«
71 I**
72 I»»
73 I
74 I*
75 I*
76 I
77 I Min. = 49°F
78 I Max. = 75°F
79 I Mean = 61.5°F
80 I
811 Detroit, Michigan Metropolitan Airport
82 I Elevation 633 ft.
83 I
84 I
85 I
86 I
87 I
88 I
89 I
I.... + ....!.... + ...'. I.... +....!.... +....!....*...,
Figure 8 Distribution of Min. Daily
Temp. - Detroit
-------
A-9
NO. OF DAYS
TEMP.
OIFF 0 10 20 30 40 50
I»«»»*»»««I»»««*«»«»I»«»»*«»»»I«»»»*«»««I.«•.*«•«•!
1 I
21-
3 I
4 I
5 I
6 I
7 I
« I
9 I*
10 I»«
11 I
12 I
13 I»
14
15
16
17
18 {««««««
19 i »•»»««««««
20
21
23 I«»****»
24
25 I
26 I
27
28 !•
29
30
31 I»*
3? T»» Mln. = 9°F
•33 !»» Max. = 38°F
3^ j Mean = 22.1°F
35 I*
2^ T Detroit, Michigan Metropolitan Airport
37 I
-------
A- 10
NO. OF DAYS
MAX
TEMP 0 10 20 30 (+0 50
I***«'f>>**I****'*'*««*I*»**>»*«*I««*«'*'««««l**>> + ,«>»I
65 I
66 I
67 I
68 I
69 I
70 I
71 I
72 I
73 I
74 I
75 I
76 I
77 I
78 I
79 I
80 I
81 I
82 I
83 I*
84
85 I*
86 I*
Q7 j
88 I
99 i
90 I *•** *•* * * •»**
91 i »»«««»«'«
92 !»*»»»*«*
93
95 {»#»«»«««««»»««««««
96 !»»»»»»»*
97 I »«*»»
98 !«»»* , Min. = 83°F
99 I Max. = 98°F
100 I Mean = 92.1°F
101 I
10? I Houston, Texas Intercontinental Airport
103 I Elevation 96 ft.
104 I
105 I
106 I
107 I
108 I
109 I
Figure 10 Distribution of Max. Daily
Temp. - Hpuston
-------
A-ll
NO. OF DAYS
MIN
TEMP 0 . 10 20 30 40 50
!••• •> + *•*• 1 ••••^••••.[••••^••••I**** + »««*I****+««9*I
45 I
46 I
47 I
<*8 I
49 I
50 I
51 I
52 I
53 I
54 I
55 I
56 I
57 I
58 I
59 I
60 I
61 I
62 I
63 I
64 I*
65 I
66
67
68
69
70
71
~fp
73 j •»»•»•»«••»••»•»•»•»»
74 ]«••»*•»«•»•»•»*•«•
75 |»««»
76 !»*»
77 I»»
78 I*
79 I
80 I Min. = 64°F
81 I • Max. = 78°F
8^ I Mean = 71.3°F
83 I
84 I Houston, Texas Intercontinental Airport
85 i Elevation 96 ft.
86 I
87 I
88 I
89 I
Figure 11 Distribution of Min. Daily
Temp. - Houston
-------
A-12
NO. OF DAYS
TEMP
DIFF 0 10 20 30 40 50
I««»»+»»»»I»»»«+»»»»I«»»«*»««»J»»»»*»««»I»««»+»«»«I
II
?. I
31
4 I
51
61
71 •
81
9 I
10 I
11 I
* 12 I***
13 I**
14 I <»»««•»
1 5 i «•»•»•»
17 I
18 I ********
20 I »»»*»»****•**•**
21 i •»*•»»»•»*»»»*
2? I
23
24 I »*•»»•»**
25
26
27
28 I**
29 I»
30 I*
31 I
32 I
3.3 I
34 I
35 I Min. = 12°F
36 T Max. = 30°F
371 Mean = 20.8°F
38 I
3<* ^ Houston, Texas Intercontinental Airport
^° I Elevation 96 ft.
41 I
42 I
43 I
44 I .
45 I
Figure 12 Distribution of Daily
Diff. Temp. - Houston
-------
A-13
NO. OF DAYS
MAX
TEMP 0 10 20 30 40 50
I..••*»«»«I»«»»*»».»I.•••*••••!•••• ****»I*««t + «.**l
65 I
66 I
67 I
68 I
69 I
70 I*
71 !•»»•»•»
72 I******************
* -J* L
74 I •»•»«•»•»•-tn* »»•»«• •»«•»•«•*•»«••»
75
76
77
78 j»«»tt*
79 I*
80
81
82
83
84
85 I*
86 I*
87 I*
88 I
89 I
90 I
91 I
92 I
93 I
94 I
95 I
96 I
97 I
98 I Min. = 70°F
99 I Max. = 87°F
100 I Mean = 75.2°F
101 I
1^2 I Los Angeles, California International Airport
103 I Elevation 97 ft.
104 I
105 I
106 I
107 I
108 I
109 I
Figure 13 Distribution of Max. Daily
Temp. - Los Angeles
-------
A-14
NO. OF DAYS
MIN
TEMP 0 10 20 30 40 50
I.... + ....I.... + ....I.... + ....I.... + ....I..., + .... I
45 I
46 I
47 I
48 I
49 I
50 I
51 I
5? I
53 I
54 I
55 I
56 I
57 I
58 I**
59 I*
60
61
62 I
63 I#***•»«•»*•»•»•»•»*•&»•»«••&«*•»»»«• #•»••»
64 I *»»•»»»•»»»**•»»*«*
65 I*»•»»•»•»«**•»
66 I*»»»*«**»»»
67
68
69 !«*«•
70 I«
71 I
72 I
73 I
74 I
75 I
76 I Min. = 58°F
77 i Max. = 70°F
78 I Mean = 63.4°F
79 I
y0 | Los Angeles, California International Airport
81 I Elevation 97 ft.
82 I
83 I
84 I
85 I
86 I
87 I
88 I
89 I
Figure 14 Distribution of Min. Daily
Temp. - Los Angeles
-------
A-15
NO. OF DAYS
TEMP
OIFF 0
10
20
30
40
50
1 I
2 I
3 I
4 I
5 I
6 I
7
8
9 j •»•»» •» «••»«• •»•»«••»
10
I
I*
I*
12 J
13 !«««««««*
14
15 !»*«
16
17
18
19
20
21 I
22 I
23 I
24 I
25 I
26 I
27 I
28 I
29 I
30 I
31 I
32 I
33 I
34 I
35 I
36 I
37 I
38 I
39 I
40 I
41 I
42 I
43 I
44 I
45 I
Mln. » 7°F
Max. = 27°F
Mean = 11.9°F
Los Angeles, California International Airport
Elevation 97 ft.
Figure 15 Distribution of Daily
Diff. Temp. - Los Angeles
-------
A-16
Table 1. 60 min., 64-84°F Heat Build Test Data (with 60% Tank Fill).
Table 1-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000 010 020 030 0*40 050 060 070 080 090 100 110
64.00 67.20 70.50 73.90 77.30 80.20 83.80 84.90 84.80 84.20 84.20 84<50 84.50
64.00 67.50 70.90 74.50 76.80 80.10 84.00 84.80 84.20 B4.20 84.20 84*50 84.50
64.00 67.00 70.10 74.00 76.40 80.00 83.00 84.50 84.60 84,50 84.20
64.00 67.00 71.00 74.20 77.30 80.00 83.00 84.80 85.00'84.80 84.50 84,80 84.50
NO. TEST 44 44 44 4 4 4 33 4 4
MEAN 64.00 67.17 70.63 74.15 76.95 80.07 83.45 84.75 84.65 84.40 84.30 84,57 84.42
Table 1-B. Vapor Temperatures, °F, at the Following Times, Min.
000 010 020 030 040 050 060 070 080 090 100 110 120
70.00 70.90 72.90 74.50 76.90 78.80 81.30 82.80 83.30 83.20 83.20 83,80 83.60
69.80 70.50 73.10 75.20 76.30 79.10 81.70 83.10 83.10 83.00 83.00 83.50 83.50
70.50 70.80 72.80 75.00 76.70 78.90 81.00 82.90 83.40 83*40 83.70
70.80 70.90 73.30 75.80 77.50 79.10 81.20 83.00 83.80 83.80 83.50 83^80 83.90
NO. TEST 4444444443344
MEAN 70.37 70.77 73.02 75.13 76.85 78.97 81.30 82.95 83.40 83.33 83.23 83i63 83.67
Table 1-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120
0.0 1.57 4.42 6.91 10.33 14.03 18.23 21.7fl 23.08 23.43 23.43 23i49 23^77
0.0 2.42 5.76 9.55 13.92 18.39 23.73 27.36 28.73 29.32 29.82 30.13 30.63
0.0 1.44 3.58 6.23 9.60 13.25 17.70 20.62 21.61 21,76 21.77
0.0 1.65 4.30 7.52 11.38 15.63 20.41 24.35 25.55 25.99 26.50 26J64 27.06
NO. TEST 4 4 4 4 4 4 4 4 4 3 3 ~~T~4 4
MEAN o.O 1.77 4.51 7.55 11.31 15.32 20.02 23.53 24.74 26.25 26.58 25;5o 25.81
-------
A-17
Table 2. 60 min., 64-84°F Heat Build Test Data (with 40% Tank Fill).
Table 2-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110
120
64.00 69.60
64.00 69.00
64.00 68.00
64.00 66.00
64.00 67.30
64.00 68.00
72.00 75.80
71.50 75.20
71.00 74.20
71.20 74.90
70.20 73.70
71.20 75.00
78.80 82.40
78.10 81.20
78.10 80.80
78.00 80.50
77.30 80.80
77.90 80.80
85.00 85.60
85.00 85.80
84.00 84.00
84.20 84.50
83.50 84,00
84.00 84.50
85.80 86.10
85.60 85.50
84.30 84.20
84.80 84.50
84-00 84,20
84.30 84.60
85.80 85*30 85.20
85.50 85.70 85.50
84.50 84ilO 83.80
84.00 84.00 84.20
84.20 84.00 83.80
84.40 84.30 84.00
NO. TEST 6 6 6 6 66 6 6 6 6 6 6 6
MEAN 64.00 68.30 71.18 74.80 78.03 81.08 84.28 84.73 84.80 84.85 84.73 84.57 84.42
Table 2-B. Vapor Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100
110 120
70.00 71.*0 73.80 75.80 77.80 79.70 81.20 82.10 82.70 83.80 84.00 83;40 83.40
7l!30 72.20 74.50 76.00 77.90 79.50 81.20 82.90 83.20 83.70 84.00 84.10 84.20
69.00 70.00 72.80 74.20 77.00 78.00 80.80 81.90 82.80 82.90 83.40 83.30 82.80
69 80 71.20 73.90 75.80 77.80 79.20 81.30 82.80 83.30 83.00 83.00 83.30 83.10
ll'.lo 70 IS ll 80 74:50 77 00 79.20 81.00 81.90 82.80 83.00 83.30 83.30 83.00
69.50 7UOO 73.80 75.80 77.80 79.60 81.30 82.80 83.30 83.50 83.50 83.30 83.00
69.93 71.10 73.60 75.35 77.55 79.20 81-13 82.40 83.02 83.32 83.53 83.45 83.25
Table 2-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100
110 120
NO. TEST
MEAN
0.0
0.0
0.0
0.0
0.0
0.0
6
0.0
2.74
1.99
2.74
3.02
2.45
3.10
6
2.67
5.93
5.48
5.77
6.47
5.20
6.20
6
5.84
9.40
8.75
9.39
10.12
8.94
9.94
6
9.42
13.17
12.60
13.36
14.37
12.99
13.68
6
13.36
17.48
16.43
17.53
18.40
17.06
17.86
6
17.46
23.54 26.93 28.66
22.06 25.95 27.11
22.78. 26.62 28.13
23.91 27.64 29.44
22.45 26.64 27.83
22.55 26.38 27.44
666
22.88 26.69 28.10
29.36
27.60
28.83
30.16
28.18
28.25
6
28.73
29.59
27.74
28.80
30.88
28.88
28.55
6
29.07
29^82
27.79
29.39
30:86
29.25
28;70
6
29.30
30.17
29.16
30.10
30.98
29.66
29.22
6
29.88
-------
A-18
Table 3. 60 min., 60-84°F Heat Build Test Data (with 60% Tank Fill)
Table 3-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120
60.00 65.00 68.00 72*00 76.50 80.80 84.80 86.00 85.30 85.80 86.00 86*00 85.20
60.00 63.60 67.70 71.90 75.80 79.00 83.30 85.20 85.50 85.20 85.00 85,20 85.30
60.00 63.80 67.50 72.00 75.80 79.50 83.80 85.20 85.80 85.80 85.80 85.20 85.20
60.00 63.80 67.80 72.00 76.00 79.20 84.00 85.80 86.00 85.80 85.60 85,80 85.80
.NO. TEST 4444444444444
MFAN 60.00 64.05 67.75 71.97 76.02 79.63 83.97 65.55 85.65 85.65 85.60 85.55 85.38
Table 3-B. Vapor Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120
66.00 68.70 70.50 73.50 76.00 78.80 81.40 83.00 83.20 83.80 84.00 84,20 83.80
68.20 69.20 71.00 73.80 75.80 77.80 80.10 82.80 83.10 83.20 83.20 83,70 84.00
68.30 68.80 70.80 73.50 75.80 78.00 80.50 82.80 83.70 83.60 84.00 83.80 83.80
67.70 68.00 70.50 73.00 75.40 77.60 80.30 82.80 83.50 83.50 83.80 84.00 84.10
NO. TEST 4444444444444
MEAN 67.55 68.67 70.70 73.45 75.75 78.05 80.57 82.85 83.38 83.52 83.75 83:92 83.92
Table 3-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120
NO. TEST
MEAN
0.0
0.0
0.0
0.0
4
0.0
1.29
1.43
1.49
1.30
4
1.38
4.16
4.43
4.34
3.89
4
4.20
7.28
8.30
7.75
7.57
4
7.72
11.46
13.09
12.15
11.62
4
12.08
16.56
18.31
17.27
16.50
4
17.16
21.80
25.23
23.71
22.97
4
23.43
26.49 27.93 28.66
30.44 32.36 33.59
28.61 30.46 31.46
27.88 29.24 29.99
444
28.35 30.00 30.92
29.36
34.15
31.81
30.12
4
31.36
29.43
34.83
31,99
30*45
4
31i67
29.59
35.J4
32.35
30.84
4
31.98
-------
A-19
Table 4. 60 min., 60-84°F Heat Build Test Data (with 40% Tank Fill)
Table 4-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000
010 020 030 0^0 050 060
120
60.00 65.20 69.30 73.80 77.50 81.50 85.80 83.60
60.00 65.20 69.00 72.20 76.50 80.20 83.50 82.40
60.00 65.40 68.90 72.20 76.10 79.90 83.90 82.50
60.00 65.50 68.50 72.80 75.90 80.00 83.50 82.90
60.00 66.00 69.50 73.80 77.00 80.20 84.00 83.20
NO. TEST 55555555
MEAN 60.00 65.46 69.04 72.96 76.60 80.36 84.14 82.92
Table 4-B. Vapor Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 120
69.00 69.80 72.70 74.70 77.00 79.00 81.60 82.60
68.00 69.00 72.40 74.50 76.90 79.00 81.10 81.80
68.10 69.10 72.30 74.00 76.50 78.90 81.00 82.00
67.90 69.00 72.00 75.00 76.10 79.00 80.90 82.00
68.20 69.80 73.30 75.90 77.20 79.20 81.20 82.20
NO. TEST 55555555
MEAN 68.24 69.34 72.54 74.82 76.74 79.02 81.16 82.12
-------
A-20
Table 4-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020 030 040 050 060 120
0.0
0.0
0.0
0.0
0.0
3.42
3.36
3.02
2.67
2.89
7.64 12.?7 17.10 22.95 29.68 43.08
7.02 10.73 14.78 19.72 25.20 36.95
6.47 9.71 14.23 18.70 24.42 34.21
5.50 8.46 11.93 16.25 21.31 27.72
6.50 10.04 13.73 18.21 23.27 34.65
NO. TEST 55555555
MEAN 0.0 3.07 6.63 10.24 14.35 19.17 24.78 35.32
Table 4-D. Tank Pressure, in. H20, at the Following Times, min.
000
010 020 030 040 050 060 120
NO. TEST
MEAN
0.01
0.0
0.0
0.0
0.0
5
0.00
0.20
0.20
0.20
0.18
0.21
5
0.20
0.09
0.04
0.03
0.03
0.03
5
0.04
0.13
0.07
0.07
0.07
0.08
5
0.08
0.16
0.10
0.10
0.10
0.10
5
0.11
0.21
0.13
0.13
0.13
0.13
5
0.15
0.28
0.18
0.17
0.18
0.18
5
0.20
0.0
0.0
0.0
0.0
0.0
5
0.0
-------
Table 5. 120 min., 60-84°F Heat Build Data (with 40% Tank Fill)
Table 5-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000 010 020 030 040 * 050 060 070 080 090 100 110' . lc»
«>«•«•*» .••»•«•<•»> ••••• • <•*«•• •»•»••••• «••••»«- »*•• W*» •••»• «» «•••••
60.00 64.30 66.50 67.80 69.10 71.00 72.30 74.00 76.50 78.30 80.40 81.80 83.20 83.30
60.10 63.90 66.50 67.90 69.00 71.00 72.20 74.50 76.80 78.20 80.00 81J70 83.90 83.50
60.00 64.00 66.30 68.00 69.10 71.00 72.70 74.50 76.60 78.10 80.10 82*00 84.00 83.00
60.00 64.50 67.00 68.60. 70.00 71.50 73.00 74.90 77.00 78.90 80.30 82*00 84.00 83.20
NO. TEST 44 4 4 4 4 44 4 4 4 4 4 4
MEAN 60.02 64.17 66.57 68.07 69.30 71.13 72.55 74.47 76.,72 78.38 80.20 81*88 83.77 83.25
Table 5-B. Vapor Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120 180
68.00 68.80 70.80 72.00 73.00 74.00 75.10 76.00 75.60 78.90 80.00 80i60 82.00 82.60
68.00 69.00 71.30 72.90 73.10 74.00 75.10 76.50 77.80 78.70 79.80 80.20 82.00 82.80
69.10 69.80 71.60 73.00 73.60 74.30 75.80 76.50 77.70 78.50 79.90 80*80 82.00 82.60
69.00 70.00 72.00 73.80 74.10 74.90 75.90 76.90 78.10 79.10 80.00 80.90 82.00 82.20
»••«"»••" •«••»•»•'•»••••• V«0»B*> . W«M*» M _••« W WMH « •»•» •••••»• ••«• W •••«••»•• ••>••<••» MM Wl» •<•••»••• • • • •
NO. TEST 44444444444444
MEAN 68.52 69.40 71.42 72.92 73.45 74.30 75.47 76.47 77.30 78.80 79.92 80^63 82.00 82.55
_
i
NJ
-------
NO. TEST
MEAN
Table 5-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120 180
0.0 2.59 4.32 5.61 6.83 ft. 85 10.64 12. BO 14.95 17.38 19.38 22.05 25.00 29.28
0.0 2.30 4.45 6.03 7.39 9.33 11.20 13.29 15.81 18.24 20.83 23.97 27.04 31.93
0.0 3.37 5.96 7.90 9.55 12.07 14.29 16.88 19.32 22.13 25.54 28:61 32.14 37.92
0.0 2.38 4.61 6.33 7.41 9.00 11.01 12.80 14.94 17.24 19.62 22*27 25.36 28.51
4 4 4 44 4 4 4 4 4 4 4 4 4
0.0 2.66 4.83 6.47 7.79 9.81 11.78 13.94 16.25 18.75 21.34 24;22 27.38 31.91
Table 5-D. Tank Pressure, in. 1^0, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120 180
NO. TEST
MEAN
0.0
0.0
0.01
0.0
4
0.00
0.06
0.07
0.12
0.10
4
0.09
0.0
0.0
0.01
0.01
4
0.01
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.01
0.01
4
0.01
0.0
0.0
0.0
0.0
4
0.0
o.o
0.01
0.0
0.0
4
o.oo.
0.0
0.0
o.o
0.01
4
0.00
0.0
0.01
0.01
0.0
4
0.01
0.0
0.01
0.01
0.0
4
0.01
o;o
0.03
0:03
0*01
4
0:02
0.01
0.03
0.03
0.03
4
0.02
0.0
0.0
0.0
0.0
4
0.0
Ni
NJ
-------
Table 6. 180 rain., 60-84°F Heat Build Test Data (with 40% Tank Fill)
Table 6-A. Liquid Fuel Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120 130 140 150* 160 170 180
60.00 64.00 66.10 67.50 68.10 69.10 70.00 70.90 71.50 72.90 74.20 76,00 77.50 78.00 79.00 80.60 81.00 83.00 84.00
60.00 63.30 65.50 66.80 67.80 69.10 70.30 71.00 71.50 73.00 74.50 75;50 77.50 78.10 79.20 80.10 82.00 83.20 84.30
60.00 64.50 66.80 67.50 69.00 70.00 71.00 71.80 72.10 73.20 74.70 76:20 77.50 78.50 79.20 80.80 82.20 83.20 84.70
60.00 64.20 66.30 67.00 68.20 69.90 70.30 71.00 71.50 73.00 74.80 76,10 77.20 78.20 79.20 80.20 81.80 83.20 84.10
NO* TEST 4 4 4 4 444 4 4 4 4 4 4 4 4 4 4 4 4
MEAN 60.00 64.00 66.17 67.20 68.27 69.52 70.40 71.17 71.65 73.02 74.55 75^95 77.42 78.20 79.15 80.42 81.75 83.15 84.27
t-o
u>
Table 6-B. Vapor Temperatures, °F, at the Following Times, min.
000 010 020 030 040 050 060 070 080 090 100 110 120 130 140 150 160 170 130
67.50 68.70 70.80 71.90 72.90 73.20 74.10 74.50 75.00 74.90 76.30 77,10 78.80 79.00 79.00 80.30 81.20 82.00 82.40
67.80 69.00 70.70 72.00 72.70 73.80 74.50 75.20 75.20 75.90 77.00 77J80 78.80 79.00 79.80 80.20 81.90 82.50 83.00
69.30 70.20 72.30 73.00 73.80 74.80 75.50 76.00 76.00'76.00 77.30 78.20 79.00 79.80 79.80 80.50 81.80 82.50 83.50
67.80 69.20 71.20 71.80 73.20 73.80 74.70 75.00 75.20 75.80 76.80 77^50 78.50 79.00 79.40 80.00 81.20 82.00 82.30
*•»•••» — <••• •» — ••••• *••<•>• ••»••••• •.»•* •« v». •»•_•« • •••••. •»•»••«»* •••*•• •»*_«« -••«'.« •••»•»•• w w*v •>•»•••• •••••• •••*• ^ •»••!• • •••»•• «»••••
NO. TEST 4 4 4 4 4 4 4 44 44 4 4 4 44 4 4 4
MEAN 68.10 69.27 71.25 72.17 73.15 73.90 74.70 75.17 75.35 75.65 76.85 77*65 78.77 79.20 79.50 80.25 81.52 82.25 82.80
-------
Table 6-C. Hydrocarbon Loss, grams, at the Following Times, min.
000 010 020
030
040 050 060 070 080 090 100 110 120 130
140
150 160 170 180
NO. TEST
MEAN
0.0
0.0
0.0
0.0
4
0.0
2.59
1.70
3.55
2.03
4
2.47
4.74
3.84
5.97
3.85
4
4.60
6.47
5.62
8.11
5.32
4
6.38
7.91
6.89
9.82
6.90
4
7.88
9.34
8.10
1U24
8.13
4
9.20
10.42
10.00
12.65
8.42
4
10.37
11.50
10.92
13.92
10.16
4
11.62
„
12.58
12.22
15.08
11.11
4
12.75
14.39
13.77
16.71
12.56
4
14.36
16.17
15.61
18.63
14.22
4
16.16
17.94
17,05
20.45
15:88
4
17i83
20.09
19.05
22.57
17.46
4
19.79
22.05
20.85
24.78
19.21
4
21.72
24.44
22.98
26.80
21.84
4
24.02
26.69
25.19
29.13
22.83
4
25.96
29.26
27.38
31.37
25.49
4
28.38
31.56
29.79
33.78
27.36
4
30.62
34.0
32.70
36.56
29.09
4
33.19
I
N3
000 010
Table 6-D. Tank Pressures, in. 1^0, at the Following Times, min.
020 030 040 050 060 070 080 090 " 100 110 120 130 140
150 160 170 180
NO. TEST
MEAN
0.0
0.0
0.0
0.0
4
0.0
0.04
0.0
0.09
0.04
4
0.04
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0*0
0,0
0,0
0,0
4
0*0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
o.o
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
0.0
0.0
0.0
0.0
4
0.0
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