DEMONSTRATING ASPECTS
OF SMALL ENGINE OPERATION
A PROJECT REPORT
SUBMITTED IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR
SENIOR HONORS PROJECT
by
GLENN C. SMITH
ADVISER - DR. KENNETH E. POUCHER
BALL STATE UNIVERSITY
MUNC IE. INDIANA
JULY. 1971
:,
'
I
"
"
I recommend this project for acceptance by the
Honors Program of Ball State University for graduation
with honors.
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- :Gl';f~~er
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Department of
Ind~trial
and 'rechnology
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Education
'rABLE OF CONTENTS
List of Tables
•
List of Figures
• • • • • •
•
• •
The Project
• • • •
• •
•
•
• • • •
Statement of the Pro jec t
Description
Method
Findings
• • • • •
•
•
•
•
•
Appendix
iii
•
• •
• •
•
• • • • •
•
• • • •
Summary and Cone lusions
Bibliography • • • •
•
•
•
• •
• •
ii
• • • •
• • • •
Evaluation • •
•
• • • • • •
•
• •
•
• • •
•
Background Information
•
•
•
•
•
• •
• •
•
•
Glossary •
Appendix B.
Fuel Flow Chart for Pounds per
• • •
4
•
11
•
16
•
30
32
•
33
•
34
•
36
•
37
• •
38
• • • •
39
•
Puel Flow Approximation for "Low
Flow Rates
•
•
• • •
Air Flow Chart for Cubic Feet per
Minute
Appendix E.
•
• • • • •
Hour
Appendix D.
3
34
Appendix A.
Appendix C.
•
•
• •
• • • • •
1
11
•
• • •
•
• •
•
Air Flow Chart for Ounces per
Minute
i
•
•
•
LIs'r OF TABLES
TABLE 1
TABLE 2
TABLE:3
DESIRABLE COlVlBUST'ION EFFICIENCIES FOR VARIOUS
AUTOMOBILE SPEEDS
8
FUEL-AIR MIXTURE RATIO REQUIREMENTS FOR
DIFFERENT ENGINE OPERATING CONDITIONS
9
TEST RESULTS FOR ENGINE RUNNING WITH OPEN
CHOKE
ii
18
LIST OF FIGURES
Figure I. - Air Consumption in Relation to
Engin~~
Speed
5
Figure II. - Fuel Consumption in Relation to Engine Speed
6
Figure III. - Volumetric Efficiency in Relation to
Engine Speed
7
Figure IV. - Fuel-Air Ratio in Relation to Car Speed
10
Figure V. - Fuel Flow Rate in Relation to Engine Speed
20
Figure VI. - Air Flow Rate in Relation to Engine Speed
21
Figure VII. - Air Flow Rate in Relation to Engine Speed
22
Figure VIII. - Volumetric Efficiency in Relation to
Engine Speed
23
Figure IX. - Combustion Efficiency in Relation to
Engine Speed
24
Figure X. - Fuel to Air Ratio in Relation to Engine Speed
25
Figure XI. - Exhaust System Temperature in Relation to
Engine Speed
25
Figure XII. - Estimated Temperature of Burning Fuel
Mixture in Relation to Engine Speed
26
Figure XIII. - Pressure between the Throttle and Intake
Valve in Relation to Engine Speed
27
Figure XIV. - Pressure at Throttle in Relation to
Engine Speed
28
Figure XV. - Pressure between the Choke and Throttle in
Relation to Engine Speed
28
iii
THE PROJECT
Engine mounted on test stand showing air
intake pressure connections, fuel and air flow rotameters,
and surge tank.
2
Engine mounted on test stand showing the compound
gauges used for measuring pressures in the air induction
system.
STATElflliNT OF THE PROJECT
Although the various operating conditions of a
small gasoline engine are easily discussed, they are not
so easily demonstrable.
'Phe teaching aid to be constructed
will be used to demonstrate the relationships between
throttle-controlled engine speed, fuel and air flow,
volumetric efficiency, combustion efficiency, fuel-air
ratio, exhaust system temperature, and pressure conditions
existing in the air induction system at various choke
positions of a four cycle single cylinder engine.
A review of literature related to reciprocating
internal combustion engines reveals a lack of information
dealing with the relationship between throttle-controlled
engine speed and the above listed factors of engine
operation--especially for small gasoline engines.
The
project presented in this paper was designed to help fill
in some of these information gaps by providing a vehicle,
in the form of a four cycle small gasoline
enginl~,
for
demonstrating these relationships and assertaining information
for graphic illustration of the various operating aspects of
a particular engine under the conditions whjch follow.
BACKGROUND INFORMATION
Although published information dealing with the
various aspects of small engine operation under the conditions
and in the manner with which they were dealt in this project
is lacking, some information deemed helpful in defining the
aspects measured and determining the validity of the results
is summarized in the following paragraphs.
Obert discusses means of measuring fuel and air
flow, including the use of a surge tank, for internal
combustion engines 1 and gives an air consumption curve
for a six cylinder four-stroke-cycle engine at wide
open throttle. 2 An adapted version of the curve is
reproduced in Figure I.
that air consumption
It can be seen from Figure I
in~reases
to a theoreticalnaximum
at about 4500 RPM for this particualr engine and then
begins to drop.
lEdward F. Obert, Internal Combustion Engines,
pp.
36-38.
2Ibid ., p. 437.
5
1000
~---+---4---~---+---4----~--+--.--+---4---~--~
800
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II
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3000
4000
5000
Speed (rpm)
Figure I. - Air Consumption in Relation to Engine Speed
A fuel consumption curve for an eight cylinder
.
.
1
.
1
englne
lS a so glven.
An adapted version of the curve
is reproduced in Figure II.
Fuel consumption for this
engine increases almost linearly up to 2500 RPM and
then continues to increase at a lesser rate.
1 Ibid ., p. 458.
6
100,
.-~--
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90
80
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800 1200
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1600 2000 2400 2800 3200 3600 4000
Engine Speed (rpm)
Figure II. - Fuel Consumption in Relation to Engine Speed
Crouse defines volumetric efficiency as the ratio
between the amount of air-fuel mixture that actually enters
the cylinder and the amount that could enter under ideal
conditions, but uses the weight of air in ounces entering
the cylinder during each intake stroke divided by the weight
in ounces of air of the piston displacement to determine
volumetric efficiency in an example.
Crouse gives eighty
7
percent as a good volumetric efficiency for an engine
running at fairly high speed, with some engines falling to
fifty percent at high speeds. 1 Stockel defines volumetric
efficiency as the total volume of the charge divided by the
total cylinder volume (displacement).
Stockel points out
that volumetric efficiency is affected by engine speed,
temperature, throttle position, intake system design,
atmospheric pressure, etc., which he follows with an
approximate graph of volumetric efficiency for an engine at
various speeds.
100
80
This graph is reproduced in Figure 111.2
I
-- ---
...... :..------
I.
.:L
_
r---...
~
60
~\
40
20
o
500
1000 1500 2000 2500 3000
R.P.M.
Figure III. - Volumetric Efficiency in Relation
to Engine Speed
It can be seen in Figure III that volumetric efficiency
decreases markedly at high RPM.
The cross marks the
point of highest volumetric efficiency.
lWilliam H. Crouse, Automotive Mechanics, p. 72.
2Martin
w.
Stockel, Auto Mechanics Fundamentals, p. 8-5.
8
Obert defines volumetric efficiency as the weight of air in
pounds inducted per intake stroke divided by the theoretical
weight of air in pounds to fill engine displacement volume
.
1
un d er atmosp h erlC pressure.The Sun 'rune-Up Handbook gives desirable combustion
efficiencies for various automobile engine speeds--these
are listed in TABLE 1.2
TABLE 1
DESIRABLE COMBUSTION EFFICIENCIES FOR
VARIOUS AUTOMOBILE SPEEDS
RPM
Combustion Efficiency
idle
72% to 76%
800
1000
1200
78% to 82%
1500
1800
2000
2200
84% to 88%
These combustion efficiencies are given over a
relatively low speed range.
The combustion efficiency
increases twelve percent over the given range.
Obert defines the fuel-air ratio as pounds
of fuel per time t divided by pounds of air per time t. 3
10bert, Engines, p. 43.
2Sun Electric Corporation, pp. 46-47.
30bert, .2£. cit.
9
The Small Engines Service Manual gives approximate fuelair mixture ratio requirements for different operating
condi tions which are reproduced in rrABLE 2.1
TABLE 2
FUEL-AIR MIXTURE RATIO REQUIREMENTS FOR
DIFFERENT eNGINE OPERATING CONDITIONS
Fuel (lb. )
Air ( lbs. )
Starting, cold weather
1
7
Accelerating
1
9
Idling (no load)
1
11
Part open throttle
1
15
Full load, open throttle
1
13
Notice that the fuel-air ratio becomes leaner up to full
loa d, open throttle.
Crouse's graph of the fuel-air ratio requirements
of an automobile engine at different car speeds is given in
Figure IV. 2
This graph provides a curve for fuel-air
ratio requirements.
Notice that the data given in Figure IV,
though slightly different, is very similar to that in
TABLE 2.
1Kenneth F. Long, editorial director, p. 5.
2
Crouse, Mechanics, p. 151.
10
5/1
10/1
15/1
20/1
Part
o
20
40
60
80
100
CAR SPEED, MPH
Figure VI. - Fuel-Air Ratio in Relation to Car Speed
Stockel states that the burning fuel mixture in an
engine can reach a temperature of 4000 degrees Fahrenheit
and normally is 2000 degrees Fahrenheit. 1 Kuns states that
forty percent to thirty percent of the total heat given off
by the liquid fuel goes to the exhaust system.
2
'Ehe Small Engines Service Manual contains an
illustration of typical vacuum conditions in the carburetor
of a small engine operating at full throttle:
two inches
of mercury just prior to the venturi; six inches of mercury
in the venturi; and four inches of mercury just after the
venturi.
1
-Stockel, Mechanics, p. 4-2.
2
p.
Ray F. Kuns and Jack T. Duvall, Automotive Essentials,
133.
3Long, p. S.
DESCRIPTION
The engine used was a Briggs & Stratton Model
Number 8B H Type Number 904046
Serial Number 23102.
This is a single cylinder, four-cycle, L-Head engine
with 7.75 cubic inches displacement, ignition timing
ten degrees before TDC, and capable of developing two and
three-quarters horsepower at 3600 RPM.
Revolutions per minute were measured using the
tachometer on the Sun 77 Small Engine Tester.
Investigation proved that the most practical method
of measuring fuel and air flow rates was the use of
rotameters in the fuel line and air path.
The specific gravity of common regular gasoline
at STP is .738; its kinematic viscosity at STP is ten
centistokes.
The operating temperature and pressure of the
fuel was assumed to be STP and a maximum fuel flow rate
of one cubic centimeter per minute was assumed to use
with manufacturer's details and sizing curve to specify
a rotameter with a maximum flow capacity of J65 pounds of fuel
per hour.
12
Selected was a SK Instruments 20-'1050V 1/:3-15-G-5
purge rotameter with a black glass float, five inch scale
of one hundred equal divisions, and an accuracy of plus or
minus two percent of the full scale.
To estimate an air flow rate, the engine was assumed
to have an eighty-five percent volumetric efficiency with
a speed range of 0-4000 RPM.
At maximum speed this would
yield a maximum air flow rate equal to:
displacement (cubic inches) x maximum RPM x volumetric efficiency
1'128 cubic inches per cubic foot
or
'1.'15 cubic inches x 4000 RPM x .85
1'128 cubic inches per cubic foot
or approximately fifteen cubic feet per minute.
was
selecte~
A rotameter
which could measure an air flow rate up to
1).6 cubic feet per minute as being of sufficient size.
Selected was a SK Instruments Type 182'1 4-HCF laboratory
rotameter with a 4)-J float, 250 millimeter scale, one
inch inside diameter hose connections, and an accuracy of
plus or minus two percent of maximum flow.
A chart was
also secured which converted the scale readings to flow
rate in ounces per minute.
A surge tank of approximately 285 cubic inches was
built and inserted between the air flow rotameter and the air
13
induction system to smooth out the air flow through the
rotameter for a more accurate reading.
This was done
because the air flow on a single cylinder engine is
intermittant and causes the rotameter float to fluctuate
quite widely if a surge tank is not present.
The volumetric efficiency of the engine was
determined by the following series of calculatio:1.s:
RPM
- number of intake strokes per minute
2
cylinder air capacity (ounces)
=
displacement (cubic inches)
1728 cubic inches per cubic foot
x 1.29152 ounces per
cubic foot
or
cylinder air capacity:
7.75 cubic inches
------------------ x
1728 cubic inches per cubic foot
1.2915;~
ounces per
cubic foot
= .00579 ounces
air flow rate (ounces per minute)
air intake (ounces)
=
number of intake strokes per minute
14
air intake (ounces)
volumetric efficiency -
x 100
cylinder air capacity (ounces)
example:
)200
- 1600
number of intake strokes per minute -
2
5.0 ounces per minute
air intake (ounces)
----------1600 intake strokes per minute
- .00315
.00)15 ounces
x 100 - 58%
volumetric efficiency -
.00579 ounces
Combustion efficiency was measured using the
Combustion Efficiency Tester on the Sun 1120 Electronic
Engine Tester.
of
This scale is based on the complete burning
fuel at any given ratio of fuel and air.
Fuel-air
ratio was also read directly from this scale.
Exhaust system temperature was measured using an
Alnor Pyrolance manufactured by Illinois Testing Laboratories.
The scale ran from 0-2500 degrees Fahrenheit.
The estimated temperature of the burning fuel mixture
was derived from the exhaust system temperature which was
taken as thirty-five percent of the total heat.
Coumpound gauges were used to measure pressure
and/or vacuum at various points in the air induction system.
Gauges were finally chosen which had a range from thirty
15
inches of mercury vacuum to fifteen pounds per square inch
guage pressure in order to measure any pressure that was
above or below atmospheric.
Three Ashcroft 1014 Duraguage
gauges with one percent accuracy, three and one-half inch
dials, one-quarter inch NPT back flush mountings, and
bronze Bourdon tubes were used.
The air intake system
was tapped for gauge placement in three places:
between
the choke and throttle; at the throttle; and between the
throttle and intake valve.
The oil used in the engine during the tests was
Quaker State Super Blend SAE 10W-20W-30 HD MS.
The
fuel used was Sunoco 200 (regular) gasoline.
A counterweight weighing 5.65 pounds was used on the
end of the crankshaft to help level out the power impulses
produced during combustion and thus reduce vibration,
erratic engine operation and consequent erratic test
results.
FINDINGS
TABLE 3 following gives results of a test run with
the choke fully open and readings obtained at RPM settings
which could be measured on the small engine tachometer used
to the greatest degree of accuracy (nearest one hundred
RPM) and held constant for a time long enough for all
readings to be taken for a particular speed.
This turned
out to be a middle speed range.
Fuel and air flow rates, volumetric efficiency,
combustion efficiency, and pressure readings are all
dependent upon temperature, barometric pressure, and
relative humidity.
These variable conditions are noted
for the time the test was run.
Since the instruments
were calibrated for STP conditions, however, the findings
following are uncorrected for the variable conditions.
These corrections, though not negligible, would be small
and would probably vary for various engine speeds.
Another correction should be noted for fuel flow rate.
The rotameter was calibrated for fuel of a given specific
gravity and kinematic viscosity, but the actual specific
gravity and kinematic viscosity of the fuel used was quite
probably not that specified for rotameter calibration.
17
Again the correction would be small and variable for
various engine speeds.
Figures for fuel flow rate are approximate due to the
variation in accuracy for rotameter readings at the low
flow rates for the particular speeds the test included.
The flow rates given are from a manufacturer's suggested
method of approximating these rates from data given for
higher flow rates.
The rotameter used, which actually
should have been smaller to measure these lower flow
rates accurately, would, however, be of just the right
size for measuring flow rates for higher engine speeds-though this was not done because these would have to be
instantaneous readings.
18
TABLE 3
TEST RES UL'J'S FOR ENGINE RUNNING WITH OPEN CHOKE
Test Conditions:
Barometric Pressure - 29.86 in. Hg
Temperature - 82 0 F.
Relative Humidity - S5%
Air
Flow
Rate
(cfm)
Air
Flow
Rate
(oz ./
min.)
RPM
Fuel
Flow
Rate
(lb./
hr. )
2000
.001
2100
.001
1.2
1.6
2200
.001
1.6
2300
.001
?L~OO
Volumetric
Efficiency
( %)
Combustion
Efficiency
(% )
FuelAir
Ratio
(lb./
lb. )
Exhaust
System
'remperaEure
( F.)
80
1/13.4
450
26
81
1/13.4
500
2.1
31
82
1/13.6
700
1.4
1.8
27
82
1/13.6
700
.001
1.4
1.8
26
81
1/13.4
750
? J::C:'
.001
1.4
1.8
25
81
1/13.4
750
260('
.001
1.6
2.1
27
81
1/13.4
750
2700
.001
1.6
2.1
26
81
1/13.4
750
2800
.002
1.6
2.1
26
82
1/13.6
800
2900
.002
1.8
2.3
28
82
1/13.6
800
3000
.001
1.8
2.3
28
81
1/13.4
800
3100
.001
2.0
4.6
51
82
1/13.6
800
3200
.001
2.2
5.0
54
82
1/13.6
850
33 0 0
.003
2.4
5.5
58
82
1/13.6
19
TABLE ) (con.)
RPM
Estimated
Temperature of
Burning
Fuel
Mixture
(OF.)
Pressure
between
Choke and
Throttle
(" itl. Hg
vacuum # lb./sq.
in. )
Hi Low
Pressure
at Throttle
(" in. Hg
vacuum # lb./sq.
in.)
Hi
Pressure
between
Throttle
and Intake
Valve ( " in.
Hg vacuum # lb./sq. in. )
Low
Hi
Low
2000
1)50
0
0
0
0
15+#
14!#
2100
1400
0
0
0
lt1
6#
20"
2200
2000
0
0
0
1"
2#
12"
2)00
2000
0
0
0
0
)#
15"
2400
2150
0
0
0
0
!#
10 1t
2500
2150
0
0
0
0
!#
10"
2600
2150
0
0
0
0
0
9"
2700
2150
0
0
0
0
1"
9"
2800
2)00
0
0
0
0
0
9"
2900
2)00
0
0
0
0
1"
8"
)000
2)00
0
0
0
0
1"
8"
)100
2)00
1#
0
0
0
21t
6"
)200
2450
0
1"
0
0
2"
6"
)300
2450
0
lt1
0
0
2"
6"
20
Graphs following in Figures
v-xv
make the findings
recorded in TABLE 3 more easily interpretable •
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Revolutions Per Minute (RPM)
Figure V. - Fuel Flow Rate in Relation to Engine Speed
From Figure V, it can be seen that fuel consumption
generally increased over the speed range of the test.
21
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Revolutions Per Minute (RPM)
Figure VI. - Air Flow Rate in Relation to Engine Speed
Figure VI shows that over the speed range of the
test, air consumption increased, which was expected.
Figure VII relates the same information as Figure
VI, air flow rate, only in ounces per minute instead of
cubic feet per minute.
The flow rate in ounces per minute
is needed for calculation of the engine's volumetric
efficiency.
22
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Revolutions Per Minute (RPM)
Figure VII. - Air Flow Rate in Relation to Engine Speed
Note the break in the graph in Figure VII to
facilitate the graphing of the broad range of results.
23
+-+--1--1
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Revolutions Per Minute (RPM)
Figure VIII. - Volumetric Efficiency in Relation to Engine
Speed
Volumetric efficiency, as shown in Figure VIII, can
generally be said to increase over the speed range of the
test.
The values for volumetric efficiency are, however,
extremely low at the low end of the speed range, compared
24
to larger engines.
As no information concerning the
volumetric efficiency of a single cylinder engine is
available, however, the reason for this result is
speculative.
Possibly this result represents actual
volumetric efficiency of the small engine.
Possibly
something was wrong with the set-up for measurement.
Note that in Figure VIII the graph has been
broken to present the broad range of results.
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Revolutions Per Minute (RPM)
Figure IX. - Combustion Efficiency in Relation
to Engine Speed
Combustion efficiency, as seen in Figure IX, for
the speeds of the test is a couple of percentage points
lower than for an automobile engine running at the same
speeds.
I
!
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25
o rn
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Hevoluti ons Per iViinute
Figure X. - Fuel to Air Ratio in Relation to Engine Speed
From Figure X, fuel-air ratio seems to be about what
was expected from the data available.
900
<J.>
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850
800
P,..c:
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650
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Revolutions Per Minute (RPM)
Figure XI. - Exhaust System Temperature in Relation to
Engine Speed
0
0
26
Estimated temperature of the burning fuel mixture,
Figure XII, determined from measurement of exhaust system
temperature, Figure XI, seems to be in line with information
available for temperatures of burning fuel.
<1>
S-i
~
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><
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Revolutions Per Minute (RPM)
Figure XII. - Estimated Temperature of Burning Fuel Mixture
in Relation to Engine Speed
Note in Figure XII that the graph has been broken
to accommodate the range of data.
Findings of pressure conditions in the air induction
27
~~;:W=Ull I I t-~4--+----f-1
---+-+-
6#
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Figure XIII. - Pressure between the Throttle and Intake
Valve in Relation to Engine Speed
0
0
-.:::T
f'1
Pressure between the
Choke and Throttle
(II Inches of Mercury # Pounds per Square Inch)
I"1j
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Illro
Pressure at the
Throttle
(IIInches of Mercury # Pounds per Square Inch)
:=s:
3000 ~---
I
!:
;i~
-
I
~
t---
iii
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<Xl
29
system seem high for positions between the choke and
throttle, Figure XV, and at the throttle, Figure XIV.
It is difficult to determine whether this is due to faulty
instrumentation, faulty set-up, or actually represents
existing pressure conditions.
The conditions indicated,
however, are possible in light of the data available.
Pressures between the throttle and intake valve, Figure
XIII, seem high at low engine speeds, but this probably
can be accounted for by fuel mixture being pushed back
out of the cylinder past the intake valve during the
compression stroke, which would be noticeable at low
RPM where the valve is open for a relatively longer
period of time.
Note the breaks in the graph
accommodate the wide range of data.
in Figure XIII to
EVALUATION
This writer's experience with the project was very
beneficial as it was necessary to review small engine
fundamentals, learn about various operating aspects
of an engine and their relationships to each other, determine
measuring apparatus and units of measurement, and delineate
the testing conditions and determine validity of tests.
Out s ide of this, the project now seems of limi ted
value.
A commercially available unit which includes a
dynamometer and fuel and air flow measuring devices
seems to be much more sophisticated for the aspects covered,
although the approach is different and the aspects covered
not as broad.
It seems now, although the project accomplishes
its aims, that it is really on a springboard to redevelopment.
S om e sort of improvement is yet needed in the control of.
determining the correction factors needed for, or
re-instrumentation required for eliminating the variables
still present, as the project now hinges upon findings
of questionable accuracy.
Better methods are needed for
controlling the tests themselves, as ways to better control
engine speed and extend tests over a wider speed spectrum
for broader conclusions.
31
To make the project a really self-contained teaching
aid, more instrumentation needs to be added to the project
rather than using that available on other pieces of test
equipment--tachometer, temperature measuring device,
combustion efficiency tester, for example.
SUMlVlARY AND CONCLUSIONS
fhe findings provide experimental data to
graphically illustrate the relationship between throttlecontrolled engine speed, fuel and air flow, volumetric
efficiency, combustion efficiency, fuel-air ratio, exhaust
system temperature, and pressure conditions in the air
induction system of a small engine.
When the engine is
running, immediate operating conditions can be observed.
The project thus provides an opportunity for the student to
see the various operating aspects of a small engine.
BIBLIOGRAPHY
Crouse, William H. Automotive Mechanics. New York:
McGraw-Hill Book Company, 1970. 550 pages.
Long, Kenneth F., editorial director. Small Engines
Service Manual. Kansas City: Technical Publications,
Inc., 1966. 320 pages.
Kuns, Ray F. and Jack T. Duvall~ Automotive Essentials.
Milwaukee: The Bruce Publishing Co., 1966.
489 pages.
Obert, Edward F. Internal Combustion Engines. Scranton:
International Textbook Co., 1950. 596 pages.
Stockel, Martin W. Auto Mechanics Fundamentals. Homewood,
IlL: 'rhe Goodheart-Willcox Co., Inc., 1963.
various pagings.
Sun Electric Corporation.
60 pages.
Sun Tune-Up Handbook.
Chicago.
APPENDIX
APPENDIX A.
GLOSSARY
Bourdon tube - a mechanical device that changes shape when
pressure is applied
BDC - bottom dead center - the lower limit of piston
movement
displacement - the volume that the piston displaces as it
moves from top dead center to bottom dead center or
~d2L
~
where d is the cylinder bore and L the length
of the piston stroke
kinematic viscosity - the ratio of absolute viscosity (a
measure of the resistance of a fluid to internal
deformation) to the mass density - expressed in
centistokes
rotameter - a gauge that consists of a graduated glass tube
containing a free float for measuring the flow of a
fluid
RPM - revolutions per minute
SAE - Society of Automotive Engineers
APPENDIX B.
Instrume~ts
SK
A
FUEL FLOW CHART FOR POUNDS PER HOUR
nlVISlor,
OF
l~ () R N \\ ELL;;:)
SCHUTTE
~i E I G H T S •
_' "
CUSTO/v\ER
&
'<OERTING
PEN
; r I;
S l' L \/ A N I A
i;j
,I
---.
COMPA,NY
1 9 0 2 C
Cf r
---------------II
ORlJER NO.
ITEM
SB. ,< ORDER NO.
DATE
"
';
,,~~,
~ _i~
"
I)
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.' ...., , 1 .I! 1
!
OPERA Tli<G PRtSSURc
CkcRATING
n~-~ ~\:...
Tlt'-"C-,
TEf\,H~R,\TU"'E
r/~
NSITY
,
((
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<~'Pl R·~
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~ ~
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r ,; '.,
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,,
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.
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,
,
,
.
.'
.
COMPUTED GY fHE
SK FOR'.'.
:"~'
,lV. 5
~9
;.,
,
(\
DATA PROCESSING SYSTEM
CALIBRATION CHART
-------- .--------.J
----T---~---,-----~-
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--.---.----~_
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,
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---,--,-~--_.l__-~---._:_-- -------
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1
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o~___.-, =-io1 .02103:-.:: ~.~-5~.Ob-.~:7Jo8-.09~-;~ -. j~~J~!:~~HOUr)
38
APPENDIX D.
""""I.~
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,......
"
250
I
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CALIBRATION CHART
I
2"0
I
230
220
I
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210-
..y. - Her
TUBE NO.
•
"".1-.]'"
n.OATNO.
CUSTOMER. ____ _
_ _ ,. _ _ _ _ _
' ... .l
~
... _ _ ., _ " ' _ _ _ _ _ .'
I
200
I
2.5
190 -
1
'fY\
-~
I
"I
~
~
170
I
~I
,
Pr)1
160
150
,"
~
, 80
2..D
~I
I
CORRECTIONS FOR HEW OPERATING COMDITIONS
FOR LIQUID
OPERATING VI,COSITY .No/oR SPECIFIC CRAVITY ARE OI'F[RENT 'RO~
~ I STED ON SCA~["A" Rt FER TO FACTORY FOR CORRECTED CA~ I •• ATI ON.
IF
OPERATING
"U~TIPLY
L I ST[D
lRE
CO"DITION5
Flews
1.15T[0
ON
"8" BY
.C"LE
---------
'" I
~
110-
::s. I
....
lor
F:'-k:
90
80 -
50 -
/.Q
S'I
;1
~I
'l,
~I
\S
I
I
"0·
I
30
I
i
•
I
I
I
0
t: '
"'-
.~!"
..:~ ..r
.
"PPLICAILE
ON
C:OIII![C:TION
.OlUMETRIC UNITS
F REf
ACTU4l
ICALI " . ' \ "
FA':TO". A'
.. L
I
GRAVII~ET'C
UNITS
F,
IIF,
F,
TEMf'E'RATURE
I/Fa
F
,
F
I/F
I
I
5
F4
./F.
I
FOR r,E'ff
G".
z
F
Gil'>
F
z
I
I
I
SPECIFIC GR4VITIES OF GASES ARE REFFERED TO AIR AT
14.7 PJIA ~ 70°F AS 1.0
PR[SSU~l
P
2
T,
T
Z
F
(P::;I
I
G)
TI
\' T
~
(PSIG)
.
TE"PERATURE
( 0
TE"P£RATuRE
i ., F)
f0N
t. )
'II
F ,")k
G
Sp.
Pi
L:QRfClI0N
O~
lIfHlcH
0 ...
B.
':.- ALl
I C I~
-I
SCALE
TO
I
IE ""DE.
B.
CORRle' I 01;
SCALE
IS
"B"
AT
IS
N[.
CAS
GJ " Sp. GR _
OF
GO"S
LISTED
G
FOR
WHiCH
FOR"
WH I C H
ON
SCALE "8" AT
CORRECTION
IS
TO
IS
TO
II.
WADE
AT S.T.P.
IE WADE
At
. . . . .•.J0,
I
O.T.P.
I
~-t, I
. • 14,' PSIA AND .,oOr
O,T,P. "OPH'4TING TLI;!PE.RATURE AHO PRESSURE
S.T.~
$eluitli UII; K~UIf
IN.TRUM.NT D,V,.'ON
50
l-
O.T.P.
fJ
,1 : .
_j-' .
COM"ANY . .
CORNWELLS HEIGHTS, BUCKS COUNTY, Pl!NN.YLVANIA
.~
1
"
~
70
MADE.
S. T. p,
CORRECTION
80
1 60-
TO IE
I
OF
.. SP, GR.
I
460
0'.
LISTED
SP. GA. o ~ GAS LISTED
•
•
L I ') -; l D
PRESSuRE
40;0
2
G,
2
+
'I - - - - - - - .
<
"
GR.
,-
,-----
P
+ 14.7
-~--" I + r 4. I
P,
,
F
PRE5',URE IIIIOR
rr""p [RA TURE &/0R
SPECIFIC GRAVITY
GAS
I
~IST[D
THOSE
PRESSUr;:E
~p.
,
""~I
100-
60 -
GAS
I~PERFECT
~
70-.
PERFECT
~
120
FRO"
8£LO ...
CORRECTION FACTOR
" I
.'
.,'
DIFfERENT
\:
130
THOI[
FO R GAS
I'
I
1"0
.
f) .,;
"
~.
APPENDIX·E.
SCALE • A"
l1QUID
~
39
AIR' FLOVl CHART FOR OUNCES PER MINUTE
liCI.~l
BAS
250
250
CALIBRATION CHART
2"0-
43-:1
,LOAT NO.
TUBE. NO.
230
7/- S3
504
:23~
2"0 230
I 220-
I
Cus rOME.R
210-
20C
190 -
190
, 80-
I
be,
.
7~
!
SO
CORRECTiONS FOR HEW OPERATING CONDITIONS
170-
r 0 R LI QlJ i I')
IF uPf~~rlkG ~ISCl~11~ AND/C~ SP[Clf Ie bR.~ITY ARE c:~rERlNT rRO~
LISTED o~ SC.L£"A" Rrr(R TC . . c:,~py 'OR CO"REef[D CALIBRATION.
160
THOSE
,0 R GAS
/.D
I ~
150
....
"; P l RAT
,riP
I
.~
:.;
-
~ .... ("3
.,
'T, ;' ~;,!)
f", ..
,.. F (
0~
.ISTt-.J
c..
I r F E. k l h T
S- .... t
"S"
By
FRO M
THOSE
!.rpL'CA.8Ll
L! S T [0
lJ N
:'ORRECi)('",
seA L E
•• B ••
FA(r:::,R
'$
I~O
~,
i 30
130
PERFECT
120
12C
1\ 0-
I
u.',
100-
,:
90
:"'P~'-"FI':
•4
F
I
70 -
v5
:~I
~,
SO
I
'j
;;.:::
"0
'. i
--.
"-
- - 3...z1
30 -
:S ~I
,
'
10
0
'. '2~1
'- I
I;)
"2l I
01
I
AT
P R £: S S \.. R.
1z
•
1; .,.. ~ .
(F
:J , ,-.; )
1.1 P l ~ A T I.J ~ E
F
90
4f,O
....:.. ._
A \'
•
\;.
" G.
b
p
2
T
Z
G
G
T(
1 F·";;.,o ...... ,1
lCr.r.tCTI,lN
,
. l
Sp
G
G
EJ
t
T
3
4
Sp
GR
.,F
~ '" ~ ft
GR
.J'
,,,1- ~.,
,-::>=1
, uR
~,
~JI
20
Alh
1(J
e,
'
p
\
p
~I
60 -
•
r1
,1
.~
IOu
(J",SE:.5 At.:F :;~;;FFREO
P'f I ~ 'I 7 n c.
AS 1.
C'
r------!
1/;
80
~-RA~lTIE:,
.
,.
'j
4,
.. ,
IC'"
T.;'.
•
S
f
"
,- ...
' " .H'
0
ON
1"
'7
F S
C(J~I(E.r
:i C ~ \.. (
[')f(kEC; I
I
c_
•. B·6
,<
A .. "" to
.. B"
T0
Il.
T
.i
IS
70
bt:.
.... ACE
S. T . ., .
c,~
,
S
A'
0.1
B !.
MADE
TQ
rJ "J
ijl
..... 01:.
•
T '.
T
"
P.
AT
O. T P
-; ('I 0 F
{) T
Sclwtte Qllt/ ,tOe~f
-----
20
COM,.ANV
INaTRUMI!NT D I V l a I O N - - - - - - - - - - -
CORNWELLS HEIGHTS, BUCKS COUNTY, PENNSYLVANIA
'-------------------.
i :'
b"