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THE US£ «N‘VxATER
AS. AN AMLDETONANT

Thesis for the Degree of M. 5.

Marion Louis Fast

1928

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TEE? USE OF 1'7 ATTI‘L AS A17 AI’TI-DTTI‘OZTAYT.

A Thesi" Submitted to the Faculty
of the
Michigan State College
of

Agriculture and Applied Science

By
”E Marion Louis‘East

Q‘fgj Candidate for the Degree

of

Easter of Science

 

June 1928.

THESiS

Acknowledgments.

I wish to take this Opportunity to thank
Professor G. A. Goodenough of the University of
Illinois for the loan of tables used in the compug
tations, Professor G. W. Hobbs for valuable advice and
assistance in running the tests and the Rec Motor Car
Co. for the loan of equipment used in running the tests.

THE AUTHOR .

9%3289

Table of Contents.

Subject Page.
Introduction 1.
Object of Investigation 3.
Equipment and Apparatus 3.

Tests to .etermine the Value of
Water as an Anti-Detonant 13.
Tests to Determine the Effect of
Water upon the Operating Characteristics
of the Actual Engine 19.

Calculations to Determine the Effect

of Water upon the Ideal Otto Cycle 22.
Conclusions 26.
Appendix 28.

Sample Computation BO.

Table
Table
Table
Table

Table

be,

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Figure

Figure

Figur

II

III

\JJ N H

“a

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10

Index to Tables.

Index to Figures.

Page.
4.

l4.
17.

20.

Introduction.

Host automobile drivers have noticed that the engine
runs smoother on damp rainy days or at'night than on hot
dry days. It has often been suggested that water he used

ces

M

to give this advantage at all times. Several dev
are on the market at the present time which supply some
moisture to the fuel charge. Report To. 45, Pat. Adv.
Com. for Aeronautics, contains the results of some tests
1ade by V. W. Drinkerhoff on a class B, U. S. Army truck
engine with a compression ratio of 3.71 to 1. He found
that the injection of water into the intake manifold had
little effect on power or efficiency for quanities of
water up to 0.4 pounds per pound of gasoline. For
amounts of water above 0.4 pounds there was a decided

decrease in power.

Host automobile carburetors are adjusted to give a
rich, power mixture. Any decrease in the richness of

t

D~d

1is mixture will result in an increase in economy.
Consequently, it is probable that any increase in fuel
economy obtained with the various water supplying devices
is due to the extra air supplied by them rather than to

the effect of the water.

2.
For years the makers of oil engines and kerosine
engines and tractors have used water to prevent pre-
ignition. The water is supplied by a mixer, an air
cleaner using water or by a special carburetor. Consid-
erable increase in the compression ratio of k rosine

‘

0v this use of water to prev-

U

tractors has been effected
ent pre-ignition. detonation and chemical "cracking" of

the fuel.

The use of water as an anti-detonant for automobile
engines instead of tetra ethyl lead has been sugges ed
by H rc Chauvierre in an article "L'eau, antidetonant"
in La Technique Automobile et Aerienne Vol. 16, To. 129.

He gives some very interesting and favorable results

obtained from tests run on a single cylinder gas engine.

Object of Investigation.

The purpose of the present investigation is to
determine; first, the value of water as an anti-detenant,
and second, its effect upon (a) the actual engine and

(b) the ideal cycle.

Equip ment and Apparatus Used for Tests.

The experimental tests were run on a Bee Flying
Cloud six cylinder engine having a bore of 3% inches
and a stroke of 5 inches. The normal compression ratio
of this engine was 4.91 to 1. Four special heads were
obtained giving compression ratios up to about 8 to 1.
These cylinder heads are sh en in gig. I. Yumber 5 head

was never used.

The volume of each combustion space was carefully
measured by means of a burette and when necessary metal
was removed by machining to make these volumes nearly
the same for each cylinder. Table I gives the data for
these cylinder heads. They will be designated by the
numbers shown in the table and on the figure, Humber 1
is the standard head. Tests run with To 4 head were not

satisfactory, so some changes were made in the head by

grinding.

Table I.
Combustion Chamber Volumes and Observed

Compression Pressures.

Displacement of one cylinder = 41.6 cu. in.

Head Cylinder Dumber. Aver- Comp.

To. 1 2’ 3 4 5 6 age. Ratio.

Volumes in c.c.

1 173 173 173 176 173 174 174 4.91
2' 150 150 150 150 155 152 151 5.51
3 133 132 132 135 127 134 132 6.16

4before 106 110 111 110 109 109 109 7.24
4after 111 112 116 112 109 111 112' 7.08
Compression Pressures in lbs./sq.in.
Measured with Okill Compression Gage.
3 111 111 110 102 115 110 110
4before 131 130 131 122 135 132 130
4after 139 139 139 137 140 140 139
Note: the valves were ground at the same time that

the changes were made in F0. 4 head.

 

 

‘1

The engine was connected to a 100 H.P. Sprague
electric dynamometer which can be seen in Fig. 2. The
dynamometer control panel is shown in Fig. 3. The
electric tachometer and speed counter is attached to the
control panel. The automatic control for the tachometer
and speed counter and the fuel weighing device was not

used for these tests because this method of measuring

 

 

 

 

 

 

Fig. 1.

Cylinder Heads Used for the Tests.

 

 

 

Fig. 2.

General View of the Test

Equip

ment.

 

 

 

 

Fig. 30
View of Dynamometer Control Panel and FUel

Measuring Equip ment.

 

8.
the fuel required much longer runs than the gasoline
measuring pipette shown in the upper left hand corner.
The pipette held just 210 c.c. of gasoline and the time
required by the engine to consume this amount was found
with a step watch. This size of pipette is such that
it gives the gasoline consumption in pounds per hour

when a constant, 20, is divided by the time in minutes

required for it to empty.

 

 

 

Fig. 4.

General View of the Manifbld Arrangement. '”

9.
The water injected was measured by similar pipettes
shown in the upper left of Fig. 2. Three pipettes with
wolumes of 56 c.c., 105 c.c., and 210 c.c. respectively

were used, depending upon the rate of water injection.

The method of injecting the water into the intake
manifold is shown in Fig. 4. Standard cepper tubing
fittings were used and orfice plates were inserted in
them. Six sets of water injection nozzles with various
size orfices were used to obtain the desired amounts of
water. Five of these sets are shown on the front edge
of the table in Fig. 5. This method of injecting the
water was used to obtain an even distribution of the
water to the various cylinders. Each nozzle supplying

water to two cylinders.

As shown in Fig. 4 the exhaust manifold was fitted
with a gas sampling cock and a thermocouple for each
cylinder. The thermocouples were inserted into the
exhaust manifold through packing glands made of cepper
tubing fittings. The thermocouples were made of No. 22
Chromel and Alumel wire inserted in two hole porcelain
insulators. The voltage of the thermocouples was meas—
red by a laboratory type potentiometer shown in Fig. 5.

A switch board was made of six standard double pole single

 

10.
throw switches. The thermocouples were calibrated in
an electric furnace with a standardized Platinum Iridium

thermocouple.

b
The exhaust gas analysis was obtained by a bubling

.3

type Orsat apparatUs shown in Figs. 2 and 5. F0 results

of any particular value were obtained.

 

 

 

Fig. 5.

Potentiometer and Orsat ApparatUs.

 

11.

 

Fig. 6.

View of Device Used for Indicating Spark Advance.

12.
The cooling water was regulated by the thermostat
which is standard equippment for tLis engine and the
temperature was given by an indicating thermometer. The
oil pan was water cooled and the temperature of the oil

shown by another indicating thermometer.

The device for obtaining the spark advance is shown
is. 6. It consists of a ring graduated in degrees
and a slip ring and pointer. These are insulated from
the foundation and are connected in series with the high
tension lead from the Spark coil to the distributer.

The pointer is set to zero with the engine at dead center
headings are obtained by noting the point at which the
spark jumps from the revolving pointer to the graduated
ring. A'switch is provided for short circuiting the
device when it is not in use. The device was designed
by the author and was constructed in the department
sheps. A'similar device has been used at Purdue Univer-

sity.

13.
Tests to Determine the Value of Water As an

Anti—Detonant.

To determine to what extent the advantages of high
compression could be realized with water as the anti-
detonant a series of tests were run for maximum power
conditions. The engine was run with wide Open throttle
at speeds starting at about 400 R.P.N. and going up by
increments of 400 to 2800 R.P.M. and then at 3000 R.P.M.
The engine gave the most power at the latter speed and
this speed was not exceeded for fear of injuring the
engine as the stresses are considerably increased by the
increase in compression. During the tests no water was
supplied to the engine when using the standard head and
just sufficient water to prevent pre-ignition and deton-
ation when using the higher compression heads. To secure
the maximum power it was necessary to advance the spark
to a point where there was a considerable "spark knock"
in all cases. This was probably due to the slight
differences in compression pressures in the different
cylinders. The variation in these pressures can be seen
from an inspection of Table I. The compression pressures

were measured by an Okill guage.

The results of these tests for heads 303. l. 2.

and 3 are shown in Table II and graphically in Fig. 7.

14.
Table II.
Maximum Brake Horse Power Tests.

R.P.N. B.H.P. Torque Lbs. Gas.Spark Deg.Water/Gas.

corrected L?.ft. /B.H.P.hr.Advance. Lbs./1b.

Cylinder Head humber 1.

414 11.1 140.5 .756 12 0.0
795 23.5 151.2 .644 16 0.0
1230 37.0 158.0 .600 20 0.0
1595' 47.6 156.5 .583 26 0.0
1990 59.2 156.0 .573 30 0.0
2375 67.6 149.5 .569 34 0.0
2775 74.0 140.0 .587 35 0.0
2995 75.6' 152.5 .615 55 0.0
Cylinder Head Humber 2.
413 11.1 141.0 .793 15 0.50
795 24.2 160.0 .622 15 0.30
1185 36.9 163.5 .596 20 0.22
1590 47.8 158.0 .513 27 0.18
1995 61.0 160.5 .545 28 0.16
2400 71.4 156.0 .549 32 0.14
2800 78.2 146.5 .568 54 0.15
2998 79.0 138.5 .587 34 0.14
Cylinder Head Fumber 3.
474 13.7 151.5 .699 10 0.0
800 2522 165.0 .595 0 0.0
1190 38.3 169.0 .584 13 0.0
1596 50.9 167.5 .531 20 0.26
2006 63.4 166.5 .517 21 0.21
2390 73.6' 161.5 .521 24 0.19
2818 80.5 150.2 .552 28 0.34
3007 82.0 143.0 .580 26 0.32'

MICHIGAN

 

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16.
The horse power has been corrected to standard conditions
of intake temperature and barometric pressure. The power
obtained for head To. 4 was considerably lower than for
the other three due to leakage at the higher pressures
and other mechanical difficulties. The results obtained
with the first three heads were exactly what might be
eXpected for the increase in compression ratio used.
The peculiar dr00p in the torque curve is a characteris-

tic of this engine and is not due to the water injection.

To determine the effect of the increased compress—
ion ratio on the fuel consumption under driving condit-
ions a series of tests were made with the engine develo-
ping just enough power to drive the automobile on a
smooth level pavement. The results of these tests are
given in Table III and graphically in Fig. 8. There is
a considerable increase in the miles per gallon of gas—-
cline with the higher compression ratios.

A11 computations of test results were made accord-
ing to the standards of the Society of Automotive

Engineers.

17.

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19.
Tests to Determine the Effect Of Water Upon the

Operating Characteristics Of the Actual Engine.

To determine the effect Of the water in the engine
a series Of tests were run with wide Open throttle and
with varying amounts of water. The results of these
tests for 1000 R.E.M are shown in Table IV and some Of
the values obtained with a Speed Of 1000 R.P.M. are
shown graphically in Fig. 9. The results obtained with
the other heads and speeds were similar and it was
thought unnecessary to tabulate them.

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U

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w-

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that the effect Of the water on combustion could not be
determined.’ It is doubtfull if the effect would be
sufficient to be noticable as the Orsa apparatus showed
only a trace Of Carbon Monoxide when there was any

excess Of Oxygen present.

Considerable difficulty was experienced with the

ignition at the higher compressions. Finally a new

,CL

spark coil was used and this helpe to some extent.

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an ignition system designed for the compressions used.

Ifi13.
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5'1. 0

Calculations to Determine the mifect of water

upon the Ideal Otto Cycle.

The method of analysis Ior the Otto cycle developed
1 To a .2. n 1‘. m u. ..: we. .°

by Goooenough and namer in A lnegooynanic Ana ysis of
Internal-Combustion Tnjine Cycles", Bulletin 30. 160,
University of Illinois, 1927, was applied to the problem
of water injection. The assuMption was made that the
water was in the vapor state when it entered the cylinde
This was not true for the method of in ection used in
the tests, however it simulifies the computation Of the
initial conditions. his assumption entirely neglects
the effect of the latent heat of the water which would

only cause a lowering of tTe in_tial temperatuge and a

[.1

corresponding decrease of temperature through out the

(f-

ults th s effgct should not he

I—‘o

cycle. For accura

,5)
-J

"5
U)

(h,
neglected but for determining the other effects of the

water on the cycle it is permissi

The results of the calculations made in applying
the above analysis are given in Table V and graphically
in Fig. 0. A sample of the conputation and a shor

discussion of the theory, especially the adaptation to

this problem, are given in the Appendix. Subscript (l)

’0

refers to the unitial conditions at the beginning of

I

compression, (2) to the end of conprossion and the

 

Table V.

'Calculated Data.

Mols Water/M01 Gas.

0

Lbs. Water/Lb. Gas. 0

M.E.P. Lbs./sq.in.
Efficiency %

Work B.t.u./Mol Gas

Mols unburned CO 3

n" H CO 4
" 1! H2 3
n n H 4

2

180.67

36.17

775166

621
14.7

1055”

124.87

3007

632.57'

.8239
.9731
3683

92.10

09792

.9957
1.480
.175
.254

.041

l
.158

178.20

36.24

77656?

620
14.7

1053

124.83

4956

626.41

.8338
.9749
3634
90-93
.9820
.9961
1.380
.151
.264

.041

14.7

1050

124.68

4860

613.43

.8372
.9780
3543

88.61

/
09803

6

.947

166.43

36-55”

783245-

618
14.7

1047

124.52

4724

594.82

.8832‘
.9818
3416
85.35'
.9910
.9979
.983
.076
.288

~03}

10
1.379
157.73
36.73
787093
617
14.7
1044
124.37
4558
572.12
.9114
.9838
3262’
81.39
.9949
.9987

‘41L;[.. :

STATE C

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beginning of combustion, (I) to the end of constant
volume comaus tion, and (4) to the end of expa11sion.
The symbols (x) and (y) refer to the percent of carbon

monoxide and h;rd1rogen burned to carbon dioxide and water.

The results for point (3) at the end of constant

volume combustion are oota 1r ed by the use of the equation

for chemical equil i riun. From the values of x; and "3

the amounts of unbttrn ed caroon monoxic‘ e and 1 fdi‘o,_ggel'

'J

1
U

D

were calculated. The injection of we er decreases the
amount of the carbon monoxide slightly due to the lower
temperature. The increased concentration of the water
causes a slight increase in the unburned hydrogen in

spite of the lower temperature. However, this is a

very slight sloning up of the combustion of the hydregen
and can not be inte: peted as a dis so ocation of the injected
water. his effect is very small at the tenperature
oot i-ned with the ideal cycle and would be so small as
to be practically negligible at the much lower temporar

ture found in tie actUal engine.

 

 

 

 

1|.” IL“... 1.»! ..’..k. I? I. a ....4..n.|u.ofl1

IILr

Conclusions.

The results of these tes s and computations are not
necessarily conclusive but they seem to indicate that
water is a very good anti-detonant and that its effect
is not as complicated as previously believed. The
effect seems to be that of lowering the temperatures
through out the cycle due to its high latent heat and
high Specific heat and a dilution of the fuel charge.
The lower temperature and the dilution prevent pre—
ignition, detonation, and chemical "cracking" and cause
a slight increase in the completness of combustion.

The dilution probably accounts for the decrease in power
that we found with increasing amounts of water. The
freedom from carbon deposits usuelly experienced is due
to the prevention of chemical "cracking". It is doubt-
full if the water injection would have such effect on
carbon deposits previously formed. V. W. Brinkerhoff.
in the report previously mentioned. gives the results

of some tests run for this purpose. however much larger
amounts of water were SUpplied to remove the carbon than
were used for anti-detonation purposes. The power
develOped was greatly reduced and even then the removal

of carbon was very slow.

 

27.

It would be of considerable interest to run a series
of tests on an engine designed for high pressures.
Preferably a single cylinder engine as that would elimi-
nate the distribution difficulties. A high speed variable
compression engine of the type used for testing fuels
would be very good for this purpose. A study of cards
taken with a high speed indicator would also be of value.

28.
Appendix.

The only deviation from the analysis of Goodenough
and 2 her in "A Thermodynamic Analysis of Internal-
Combustion Engine Cycles", Bulletin Yo. 160, University
of Illinois, 1927, is in the computation of initial
conditions. Goodenough and Baker assume the temperature
of the residual gas to be the same as the temperature
at the end of expansion. For this investigation the
temperature ef the residual gas has been found as sugg- |
ested by Professor G. D. Upton in his discussion of the
paper "Efficiencies of Otto and Diesel Engines" by
Ellenwood, Evans. and Chuang presented at the 1927
meeting of the Oil and Gas Power Division of the American

Society of hechanical Engineers.

As far as the residual gas is concerned the action
after the Opening of the exhaust valve is a continuation
of the adiabatic expansion. Of course there is no
usefull work done but the residual gas in expanding is
doing work in pushing the rest of the gas out of the
cylinder. Or the entire products of combustion can be
considered as eXpanding adiabaticly through an orfice
which in this case is the exhaust valve. For this reason
the temperature of the residual gas is much lower than

the temperature at the opening of the exhaust valve.

29.
The equation pvk = constant was applied for determ-

.ng this temperature as it is much simpler than the

L).

in
more accurate analysis and the error incured would have
a negligilbe effect on the final results. The eXponent
k was taken as the ratio of the mean specific heats at
constant pr ssure and constant volume for the particular

temperature range involved.

The following sample of the computation shows the
method of handling the injection water. As before stated

the injected water is assumed to be in a vapor state

when taken into the engine.

For a complete discussion of this theory and method

of analysis cdsult the bulletin mentioned above.

30.

Sample Computation for Water Injection.

Otto Cycle. Expansion to Suction Volume.

1.

- I 5.

Compression Patio - V6: Heat Losses : Yone.

Fuel : CBHlB (Gasoline) with 100% theoretical air.

Suction Pressure = Exhaust Pressure - 14.7 lb./sq.in.

. 5. + =

8 002 + (9 + n) H20'+ 47.25 r2.

 

 

Fuel Mixture, hols. Products Mixture, hols.
CUHlC = 1.00 8. 002 : 8.00

02 : 12.50 9. H20 i 9.00 + n

H20 3 n 10. U2 = 47.27

r2 = 47.25 ‘ 11. n2 é 64.25 + n

n1 ; 60.75 + n

40!

Lolar Spec111c Heat'Equations:

(5) x (12) - 38.327't'38.00 x 13-3 T.
((4)1-(61) x (15) = 414.

(5) x (15)

0675-r 7.17 x 10-0 T2.

(‘1

p

o
l
O\

}_3

:fiL

n(e.35 - 0.276 x 10'3 T .423 :

2' = (16) + (17) + (18)
p(FUGl hixture) (7) .

 

(8) x (14) = 57.2 +-51.2 x 10-3 T — 4.8 x 10-5 T2.
(9) x (15) = (0.:e-+ n)(8.55 - 0.276 x 13-3 T

I

+.425 x 10-6 T3).

 

(13) x (15) = 527. 4425 + 70 x 10-6 T2.
= (% +(21) +’(2’2)
xp<Products Mixture) (11)
Let n = 10 then:
i - 7. 5717 + .4981 x lO 3 T + .1611:< 10"6 T2.

m
C:
\0
V
I

7) = 7.5120 +-.5496 x 10'3 T +-.12eo x 10'6 T2.

Temperature of Fuel Mixture = 320°
ssume: T1 = 600° T4 = 32700 p4 = 82 lb./sq.in.
Let k = 1. 28 then:

.28
=EI4'7;1.28 x 3270 = 22500

Mean Temperature bet/een 4 and 5: 2760°
’10 : Q.l(\ .- ‘

)bp (for 2766 ) ‘ , ,10

yvp (for 27600) = 7.2055

k- ‘ 2_}239 : 1 276'
_ 7. 2055

' .27”
T =3270 x {1427117geg‘ = 22500
me= (19) for 560° = 7.9011
pr = (25) for 1425° = 8.0539

A3= 3321-: 1.0195

 

Computation of Initial Conditions.

 

 

Let Tl : 60 610
“‘5. 18.75 18.44
T1
(27) - 1. 17.75 17.44
Tl - Ta 80 90
(39? X (25,- 21.02 18.57

(50)
By Graphical Interpolation:
T1 2 617° El : 17.24

C
70.75

= - 4.10 8

no 17.24 3

Composition of Peeldual Gas, Hols.

 

'l
O

,p.
,{5
l\)

002 Z 8 x :7”

1:? O - 19 X M - 1.0PO

i#2 " 74.25 " 9
4.1033 ,
J = 47.25 X 74,25 - 2.012

Charge at End of Suction, Hols.
CCHIG Z 1.COO

HqO = 11.050

F2 = 49.862
02 = 12.500

H‘
._J

t.)
I

" 74.854

32.

38.

.,
)0.
’I

40.

41.

2).

The Adiabatio Compression

Tet T2 = 1050 1040 1050 T1 = 617

6(82,02) 54.5690 54.4160 54.4666 51.7940
0(002) 59.5500 59.6127 59.6949 55. 766
¢(H20) 45.9576 44.0205 44.0829 40.6761

8(08H15) 291.2575 291.986 292.7164 256.9595
((35)+'(50)

10(22,02) 2145.5196 2146.5755 2149.4061 1982.7574
(55)x¢(002) 17.4725 17.5009 17.5451 15.6807

(54)x¢(820)485.7515 406.4265 487.1160 449.4709

n¢=(50)7-(59)+

(4O)"(411 2737.7809 2942.2993 2946.7856 2704.8285
n¢(T2)-(n¢(T1) 252.9524 257.4708 241.9551 .........

4.571 x (37) x lo,

45.

‘0

glu-

‘72 r35 = 239015?

By Graphical Interpolation:

T : 10440

 

 

 

2
1) ‘2 ~ r4
p? — (J' X ( ) A t 2) = 124.37 lb./sq.in.
- T1
= 8.4605 Atmospheres.
1 U” 7" ~ 7'4 j”
v2 = ‘1 ‘2 z (6’) f l”* X (4”) : 6,757 cu. ft.
po (45) x 144

l...

 

47.

50.

The Comhustion Process.

02 = 14.246 - 4.221x - 0.0259

- _ 4"‘\ ‘ r f'
n9 - 92.600 - 4.2214 - 19.0227
pl : 894““?0 4'80 11? : 2‘30‘2‘5'3' 459' n" : 459.862

n2' 3 14.246 51. nl+ns'1+nfl=72.55. 52. np=78.354.

T11 ‘ (‘14:. 0 fr m : ‘ fl P‘r‘: TT 7 = c. o

101:. T2 " l... -4 4~v(\-/O) J..-J.’4h)vo ‘JV(.T?) 103334,)
TT TT , _ tr : Q " " V)

111.00 + mg :12 -111 ' 4(j’k)LL‘,O

T 4590 4550 4600

e , ,
zAuD (1044 to T ) 26,608 21,058 21,452
1sugo 20,265 20,614 20. 67
AUCOQ 50 .033 36‘ . 633‘ 35‘ . 24S
ALF-'20 33.2972 329667" 33:35.8
(51) X (53) 195003914 125273758 1955;3892
4(48) x (55) 207,597 _ 211,106 214,856
5/2 (47) x (55 261,972 266.657 271.395
(48) x (54) 406,275 415,511 420,588
(47) x (55) 521.075 526,102 531,506

(48) (

\n
C\
O\
,5
F1
O
\»J
‘0
O\
J]
.p
(D
\ J
\A

(7'
008 , 82S

%

 

74.

1
A

0:13.

c(b—l

c(b-l)-(a+b)

(66)2

23(0-1)

Zb'x 2a(c-l)

(67) * (69)

(70)

(66) +

107 4
log (l-x)

il 7 (37) x (42)

d .9

(44)

966,178 50
2,855,169 2.8 7,071
2,044,698 2,041,651
.4725 .4750
1.3954 1.4141
6.6710 6.7744
2.6577 2.8055
.7698 .9182
.5926 .8451
5.5591 5.4626
14.9562 15.4495
15.5488 16.2924
5.9452 4.0564
4.7150 4.9546
.8794 .9070
.4155 .4290
.9799 .9851
14.246 14.246
3.7119 3.8284
9.8255 9.8756
.7106 .5420
1.92582 1.86700

1.0722
1.1496
5.5677
15.9581

17.1077

I—Jl
5]
C.
kn
m
N

l-—-'l
\D
\1
g...
0
O

J

NI
(‘3

102‘

1.9827?

75.

~51

C\
O

'51
-J

78.

R(x, y)

103 x

-lo;(l-x) - log ne'

_.91?79

+110“ (37) X (42)
“ 7 (44)

%103 T3 1.82661

10: Kp(co) 1.58659
L(T) = 4103 T5*’

*2

log Kp(CO) 3.21320
Dy Graphical Interpolation:
T3 = 45580

X : 0"].14:

\

3
y, = .9853
)
n8 = 92.600 - 4221x - 10.0251

ll~

3 an2

n T?
p _2_4E§ = 572.1227 lb./sq.in. =

r A: n
j 0 1U‘.:9\J

1.82901

1.32307

78.8704.

71"
I'kl o

 

9199 Atm.

79.

The Expansion Process.

Let T4 be 3270°
Let X4 3
ex

ox +v(l-X)
ox

ox 4-(l-x)

 

74

v: at... n.2,.
n n5 i--lJC .4112".

log (l-x
3. log HQTB 1"

P}
F(x.y) = log "

(1-x)-%log ne'

.. 1017
n Ttvr
+é—lo .414L_
93

Let T4 =

log Kp(CO)
L(T) = 1103 T4

(00)

+103 KP

than K-

p(wator gas) =
.994 .996
3.9343 3.9923
3-9933 3.9933
~9955 .9990
14.246 14.246
4.1957 4.2041
10.01i0 13.0150
.3403 .C269
1.33266 1.21/23

1.99739
3.77815

2.33224

H
O

\1
‘J
C"\
O\
H

\J
in
‘7)
¢'\)
(‘0
\J

F”
O
\o
“’3

3
70
o\

\4!
C\
C)
R) C1
C)
(A

m
0

\.J
\J
m
A)
.1;

1.00011

I (4”

f?
\J 0

T4

By Interpolation x

o = (water gas)

7!
t 5?-

OX

ox + (l-x)
ox

 

 

 

‘J "' 6;; + (l-x)

T4 3266
Hp(c©) 119,789

T

Hp(H2) 07,337
112(1;Y)1‘ID .8582
fiDiat. 40.6406
¢062 51-3103

93 x (49) 2026.4216

¢CO x(47) 433.1616

2
¢w20X(4o) 1056.1558
103 x 1.99778
nllog x -.Cl€74
log y 1.99944
nZlog y -.Oll23
107 r .6989?
nplog r 54.76710
(86)+(87)
-(88)

40.6597
51.3457

52.7066

54.76710

3230
119.763
1.6953
107,345
.9186
40.6787

51.3811

 

-34.797o7 -34.79783 -34.79939 -.46464

90.

C
o.)

9

+485) - (9o)

1.

T4

4.571(89)

3266

-250.4774 -250.4809

(31)+-(82)'

+(83)-r(84)

C
U

.4 _

II. M.

II.

5770.5771

83 1.5877

Lntarpolation:

 

39.
T3 = 4558

9 '201239

5772.56C2 3768.9894

40.

York Done During the Cycle.

T : 617° T = 32620
I37(c’38r—I18) at T1 = 2,147,414

n1(1-x) HV(CO) a1 T4 = 5,013
ng(l-y)fiv(32 at T4 = 2,713

nlAuCO2 : 22\
n2AuHZO 5 405:391

Work = (92) - (93) - (94) - (93) - (96) - (97) 2
Work = 787,093 B.t.u. per Hol of Gasoline.

Efficiency of the Cycle.

In:p(C"TlTlO) at 5200 : 2,143,000
0“ u
Eff. = Z§7*993 x 100 = 6.7286 g.

 

2,143,000 , 9

I
1

.ean Effective Pressure.

V4FL V; = 26,948 cu. ft. Displacement.
_'Work x J Z§7.0Q§ x 777.64

(V4-V31144 7 26,948 X 144 = 157973 1b/sq.in.

----- FiniS'----

LII. .' ‘1! _.

 

: ,LILLIFAU..,LW41412.

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