TEE T0NIVERSITY OF MICHIGAN IEDUSTRY PROGRAM OF THE COLLEGE OF ENGIEEERING CONTROL OF THE COMBUSTION OF COMPRESSION IGNITION ENGINES Abdel R..A, Fo.Tbrahin A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the University of Michigan 1960 June, 1960 IP-436

ACiKNOWTEDGEMEITS I wish to express my gratitude and appreciation to all those who have offered assistance, enceouagement and guidance during the conrse of this investigation. The author gratefully acknowledges Professor E. To Vincent, the Co-chairman of the Doctoral COnm.ttee, for his continued active interest and, suggestions which were a major factor in the completion of this work, Professor Jo A. Bolt, the coc-hairman of the committee, for his suggestions and help with the experimental parts and William Mirsky was of great help with the instrimentation portion of thie worko The author wishes to thank Professor RO A. Wolfe of the Physics Department, Professor J Lo York of the Chemical Engineering Department, and Mr I:, Bishop of the Fcd Motor Company. Help in preparation of this report by the Industry Program of the College of Engineering, The TUniversity of Michigan is gratefully acknowledged:. Acknowledgment is also due to the men of the Automotive Laboratory, who in spite of their duties, we're of help in building the experimental equipments Many thanks to the Nordburg Manufacturing Company and American Basch Ama Corporation for providaing some of the material and. parts for building the apparatuso ii

TABLE OF CONTENTS Page ACKKOWOL EGEITDGSENTT w w.es*****woe e **@**@*s@@@@@@@ @@@ ii ACKNST OF FDGES........................... v LIST OF FIGURES.............................................. v NOMENCLAT U R E................................................ vii I. INTRODUCTION......................................... 1 II. EXPERIMENTAL APPARATUS............................... 4 III. THE COMBUSTION PROCESS............................... 20 IV. CBEMICAL KINETICS OF OXIDATION OF HYDROCARBONS....... 23 V. APPLICATION OF TEE TBEORY............................ 32 VI. OPERATING CONDITIONS AND TEST PROCEDURE............. 33 VII. DISCUSSION OF EXPERIMENTAL RESULTS................... 37 Series I. Performance Test of the Engine after Modification......................................... 37 Series II. Runs at Variable Primary Injection Timing............................................ 37 Series III. Variable Primary Fuel Injection Processes......................................... 46 Series IV. Runs at Variable Cooling Water Temperature................................................. 48 Series V. Runs at Variable Speed................... 51 Series VI. Runs at Different Main Fuel Injection Timing.5........................................ 56 Series VII. Runs with Additive..................... 72 Series VIII. Runs with Variation of Energy-Cell Throat Diameter................................... 72 VIII. GENERAL DISCUSSION................................. 78 IX. SUMMARY OF RESULTS.................................. 84 iii

TABLE OF CONTENTS CONT'D Page X. CONCLUSIONS AND RECOMME NDATIONS...................... 87 Conclusions............................................. 87 Recommendations....................................... 88 APPENDICES APPENDIX I. SAMPLE CALCULATIONS........................... 89 II. ENGINE SPECIFICATIONS......................... 91 III. FUELS SPECIFICATIONS.......................... 92 IV. SOLUTIONS OF THE DI'FERENTIAL EQUATIONS (4_-9 (4 (4-10), (11)......................... 9 V. THERMAL THEORY OF EXPLOSION................... 96 VI. AIR-FUEL CYCLE................................. 102 VII. ENGINE-TEST RUNS - SERIES I THROUGH VIIII...... 105 REFERENCES..................................... 142 iv

LIST OF FIGURES Figure Page 1 General Layout of the Experimental Setup.......... 5 2 Fuel Weighing System, Control Panel, Amplifier and Oscilloscope, and Potentiometer............. 6 3 The Primary Fuel Injection Pump, its Drive and Control...................................... 7 4 Cylinder Head View............................... 8 5 Cylinder Head after Modification................ 9 6 Schematic Diagram for Automatic Fuel Weighing System..........1............................ 10 7 Schematic Diagram of Cooling Water System...... 12 8 Schematic Diagram of Lubricating Oil Cooling System......................................... 14 9 Schematic Wiring Diagram of the Oscilloscope..... 16 10 Primary Injection Valve Opening Signal as Indicated on the Oscilloscope................... 17 11 Photoelectric Cell Mounting...................... 19 12 Engine Performance after Modification (Series I). 38 15 Pictorial Traces of Pressure-Time Diagrams (Series I)...................................... 39 14 Effect of P.F. Injection Timing Upon Engine Performance (Series II).......................... 40 15 Pictorial Traces of Pressure-Time Diagrams at Various P.F./T.F.% (Series II)................... 41 16 Effect of P.F. Injection Pressure Upon Engine Performance (Series III)....................... 47 17 Effect of Cooling Water Temperature Upon Engine Performance (Series V).................... 49 18 Pictorial Traces of Pressure-Time Diagrams at Various Cooling Water Temperature (Series IV)... 50 v

LIST OF FIGURES CONT'D Figure Page 19 Effect of Engine Speed Upon Delay Period and Exhaust Gas Temperature (Series V)............... 52 20 Pictorial Traces of Pressure-Time Diagrams at Variable Engine Speed (Series V).................. 53 21 Effect of Main Fuel Injection Timing Upon Engine Performance (Series VI)........................... 57 22 Effect of M.F. Injection Timing Upon B.S.F.C. (Series VI)................................... 58 23 Effect of P.F. Injection Upon Optimum Engine Performance (Series VI).......................... 59 24 Effect of Primary Fuel Injection Upon Optimum Engine Performance (Series VI)................... 60 25 Pictorial Traces of Pressure-Time Diagrams (Series V I)....................................... 61 26-33 Pictorial Traces of Pressure-Time Diagrams (Series VI)..................................... 63-71 34 Pictorial Traces of Pressure-Time Diagrams (Series VII)..................................... 73 35 Effect of Energy-Cell Throat Diameter Upon Engine Performance (Series VIII).............. 75 36 Pictorial Traces of Pressure-Time Diagrams (Series VIII)................................... 76 37 Pictorial Traces of Pressure-Time Diagrams Runs No. 3, 190, 192........................... 80 38 Pressure-Time Diagrams (Runs 3, 190, 192)......... 81 39 Pressure-Volume Diagrams (Runs 3, 190, 192)....... 82 40 log. Pressure- log. Volume Diagrams (Runs 3, 190, 192)............................... 83 41 Suggested Injection System........................ 86 42 q-T Diagram.... 97 vi

NOMENCLATURE A Area a Number of molecules per unit volume c Specific heat d Diameter E Activation energy e Natural base of logarithm f Steric factor or volumetric fraction of residualsof combustion K, k Specific reaction rate coefficient = fz eE/RT M Molecular weight N Engine speed R.P.M. Na Avogadro's Number = 6 x 1023 no Rate of initiation reaction n Order of reaction P, p Pressure Q. Heat of reation per gram - mol. q. Quantity of heat or energy per unit time R Gas constant s Surface area T Absolute temperature t Time V Volume W Rate of reaction z Frequency of collision vii

X Thermal conductivity Parameter as defined by Equation (2) page 93. Parameter as defined by Equation (1) page 93. Angles, deg. crankangle T Time characteristics as defined on page 43. Time lag in milliseconds or degrees crank angle [ ] Concentration Subscripts p,v Refers to pressure and volume respectively o Refers to initial conditions i Refers to ignition C.W. Cooling water m Main p Primary Abbreviations b.s.f.c. B.S.F.C. Brake specific fuel consumption b.h.p. B.H.P. Brake horsepower b.m.e.p. B.M.E.P. Brake mean effective pressure B.T.C. A.T.C. Before and after top dead center respectively B.B. C. A.B.C. Before and after bottom dead center respectively F/A Fuel to air ratio (weight ratio) E. C. Energy cell viii

P.F. Primary fuel M.F. Main fuel T.F. Total fuel Vs Piston displacement R.P.M. Revolutions per minute r.p.m. deg. Degrees crank angles exh. Exhaust max. Maximum comp. Compression suc. Suction k.cal Kilo calory H.V. Heating value ix

I. INTRODUCTION In the dual cycle, a charge of air is compressed in the engine and then the fuel is injected. The air is so hot, because of the approximately adiabatic compression, that the fuel spray ignites. The word ignition as used here, covers a multitude of unknowns about how soon and how much vaporization occurs, and how fast some undefined chemical reactions take place after the injection of the fuel into the hot swirling air. The mixture in the diesel combustion chamber is far from homogeneous since it consists of air and exhaust residuals from the previous cycle, and into this mixture liquid fuel is injected. It is easy to imagine droplets of fuel enveloped by a vapor-air mixture with a large variety of ratios and fairly large pockets where there is no fuel. The photographs of Rothrock and Waldron(l) show that ignition starts in the small zones near the boundary of individual sprays where the temperature is somewhat lower than the air-compression temperature owing to heat absorption by the spray. According to (2) F. Schmidt(), the physicochemical delay is of the range 0.7 to 3 milliseconds for usual diesel fuels. Lewis(3), Granger(4), Mason(5), and many other investigators observed the relation between the formation of formaldehyde and the tendency to knock in spark ignition engines. With increasing knock intensity, the formaldehyde absorption bands increase in intensity. Formaldehyde also appears under nonknocking conditions, but under conditions where formaldehyde is not detectable, knock is never observed. -1

-2Although formaldehyde is a reaction product rather than a promoter, it is an indication of the progress of the attack on the fuel by the oxygen. Granger(4), and others, believe that a hot flame must always be preceded by a cool flame. They also observed that these cool preflames are accompanied by high concentrations of aldehydes. Their results show also that the peroxides are present in the combustion chamber during the preflame period. They also found that there is no correlation between cetane number and intermediate compounds, but there is a correlation between cetane number and the time elapsing between injection and peroxide concentration. Granger(6) in an earlier paper showed the effect of some additives to the air stream on the delay period. Of these additives some were peroxides. The most sensitive fuels to additives are the most parafinic Recent investigations by Lyn,( Royle, Schweitzer(9 ) showed that the delay period was shortened by introducing part of the fuel with the intake air. Lyn's curves showed higher fuel consumption at part loads. Schweitzer showed the effect of droplet size on the smoke limit. Corzilius(ll) observed that in a hydrocarbon-air mixture, no detectable chemical reactions occur until certain temperature and pressure conditions were reached. (12) A report on Bi-fuel combustion systems ) indicated that low cetane value fuels can be used, in engines whose compression ratio would not be normally high enough to cause ignition, by injecting auxiliary fuels into the cylinder 60~ to 120~ before the main injection.

-3The maximum output of compression ignition engines is limited by its smoke limit, the knock of the engine due to the long delay period of the fuel, and its relatively low rotating speed. All of these are handicaps in utilizing such engines in many fields particulary the automotive. The above mentioned situation indicated a need to investigate the factors affecting the combustion and devise a reliable technique to control it. It was thought that by injecting part of the fuel early in the cycle directly into the energy cell, sufficient concentration of active radicals, mainly hydroperoxides, could be prepared immediately before the main injection in order to trigger the hot flame reaction and shorten the delay period. By controlling the beginning of the ignition as well as the rate of reaction, the rate of heat addition and the point of the maximum pressure rise could be controlled. Because of the numerous number of factors to be controlled, it was decided to investigate, individually, the effect of different variables in a certain order on the engine performance. These factors and their order are given on page 33

II, EXPERIMENTAL APPARATUS A vertical single-cylinder, four-stroke cycle, liquid-cooled Nordberg Diesel engine was used in the experimental work. The engine had a bore of 4 1/2 inches, a stroke of 5 1/4 inches, and a compression ratio of 14 1/2. Other engine specifications are given in Appendix II. The general test setup is shown in Figure 1. The various systems and the methods of measurements (instrumentation) are described in the following paragraphs. A. Fuel System The engine was equipped with a second injection valve placed to inject the primary fuel into the energy cell as shown in Figures 4 and 5. An additional injection pump was used to supply the primary fuel. This pump was driven by the engine by means of a chain and sprockets (Figure 3)~ The timing and the quantity of the primary fuel could be easily altered and controlled or maintained constant during any run. Two separate fuel weighing units were used to measure the fuel rate which was injected through each valve individually. The fuel rate was determined by measuring the time required for consuming a predetermined weight of fuel. The fuel weighing unit consists of a fuel container mounted on a balance, timer and electronic revolutions counter. With the engine operating at test trial conditions, and drawing fuel from the container only, the scale weight is adjusted so that the scales are almost ready to pass through balance. At a particular point during the balancing movement, the timer and the revolution counter start;,4-.

-5Figure 1. General Layout of the Experimental Setup.

-6Figure 2. Fuel Weighing System, Control Panel, Amplifier and Oscilloscope, and Potentiometer.

Figure 3. The Primary Fuel Injection Pump, its Drive and Control.

-8Figure 4. Cylinder Headt View, Showing the Two Figure 4. Cylinder Head View, Showing the Two Injection Valves, Pressure Pick-up and Photoelectric Cell.

-9EXHAUST VALVE CHAMBER RESSURE P1CK-UP ENERGY-CELL / SECTION A-A -SUCTION VALVE CHAMBER RE INJECTION VALVE RF INJECTION VALVE HOLDER ENERGY- CELL ao —----- MAIN FUEL INJECTION Figlre 5. Clne ed fe oii VALVE Figure 5. Cylinder Head After Modification.

110 VOLTS A.C. FUEL TANK FUEL CONTAINER FROM MAGNETIC - PICK-UP ON THE: 0 DYNAMOMETER SHAFT. REVS. TIMER COUNTER. PUMP MERCURY SWITCH FUEL SUPLY TO ENGINE Figure 6. Schematic Diagram for Automatic Fuel Weighing System.

-11then the scale weight is immediately raised off the scale so that the fuel container side of the scale is heavy by an amount equal to the weight of the fuel to be consumed during the trial. As the scales again pass through balance, the timer is stopped at exactly the same point in the balancing movement. The timer and the revolution counter are simultaneously engaged and disengaged and the scale weight raised automatically through relays actuated by a mercury switch mounted on the scale beam (Figures 2 and 6). B. Cooling Water System Figure 7 shows diagrammatically the cooling water system. It is of the closed type, consisting of a water pump and a heat exchanger. The water pump is of centrifugal type, built in and driven by the engine. The heat exchanger is of the shell and tube type, and is equipped with an automatic thermostatic control to maintain the cooling water temperature constant at the water pump inlet. The automatic regulator could be set manually to maintain the water temperature at any desired level within two degrees Fahrenheit. A rust inhibitor was added to the cooling water. C. Exhaust System The engine exhaust manifold was connected to the main exhaust underground conduit by a two inch pipe. The exhaust gas temperature was measured by an iron-constantan thermocouple placed in the exhaust pipe just after it leaves the cylinder head block. The temperature was read directly on a calibrated potentiometer indicator (Leeds and Northrup) in degrees Fahrenheit.

HEADER-, GLASS TUBE AUTOMATIC --- r A WATER REGULATING VALVE' —-- PUMP [,li DRAIN'( *r ~ ~ FILLING LINE HEAT EXCHANGER LINE FROM WATER MAINS THERMOSTATIC ELEMENT Figure 7. Schematic Diagram of Cooling Water System. Figure 7. Schematic Diagram of Cooling Water System.

-13D. Power Absorbing Unit A D-C cradle dynamometer, type TLC, was used to start the engine and absorb the power output. The power output of the engine (B.H.P.) is converted to electrical energy in the dynamometer (generator) and this energy was absorbed as heat in the loading air cooled resistance grids. The dynamometer was equipped with an electric tachometer to measure the speed and a Link Unibeam to measure the torque applied on the dynamometer. The torque was read directly in footpounds on a Wallace and Tiernan gage. The average speed for accurate power determination was measured by means of a stop watch and revolution counter which was explained under fuel system. E. Lubricating Oil System The engine parts were lubricated under pressure. The lubricating oil temperature, in the engine sump, was kept constant during the course of test. Figure 8 shows the lubricating oil cooling system. The oil was drawn from the engine sump, put under pressure and divided into two parts. One part was passed through a shell and tube heat exchanger to be cooled and then mixed with uncooled oil. An automatic thermostatic regulating valve regulated the proportion of the two parts to maintain the oil mixture at the required temperature. To measure the lubricating oil temperature in the sump, an iron-constantan thermocouple was used with calibrated potentiometer indicator. F. Gas Pressure Indicator Channel A of a dual-beam cathode-ray oscilloscope was used to trace the pressure-time diagram of the gas in the cylinder. The indicator was composed of:

OIL OUT TO THE SUMP WATER OUT AUTOMATIC ----— COOLING WATER REGULATING VALVE IN HEAT EXCHANGER OIL IN PUMP Figure 8. Schematic Diagram of Lubricating Oil Cooling System.

-15a. Pressure pick-up type P-701-1, Control Engrg. Corp. b. Magnetic pick-up type 3010-A, Electro Products Lab. a. Pressure Pick-Up It consists of a thin diaphragm with two catenary-shaped depressions. Resting in the circular groove formed by the intersection of the two catenaries, is one end of a thin-wall steel tube, the upper end of which is developed into a heavy flange, clamped securely to the main body. This is the strain tube on which are cemented two 1000 ohms, single layer, strain gage windings. One winding is wound longitudinally and the other circumferentially. When pressure is applied, the strain tube is compressed along its axis and expanded around its circumference. The two windings form two legs of a Wheatstone Bridge circuit. The variation in the winding resistances, due to pressure application, changes the balancing condition across the bridge. The resulting difference in voltage is amplified and fed to channel A of the oscilloscope. b. Magnetic Pick-Up The magnetic pick-up was mounted on the fly wheel casing, with its pole close to the tip of a heavy iron pointer which was oriented to the bottom dead center. The voltage pulse generated by the rotation of the pointer was applied to the external synchronization terminals of channel A of the oscilloscope (Figures 2 and 9). G. Primary Injection Valve Opening Indicator The primary injection valve was equipped with an adjustable bouncing pin used as an electric switch. The circuit was supplied with 1.5 volts D.C. The electric signal, from the valve opening, was supplied to channel B of the oscilloscope. Figure 9 shows the circuit

PHOTOELECTRIC CELL SIGNAL P.F INJECTION VALVE OPENING SIGNAL BOTTOM DEAD CENTER SIGNAL. GAS PRESSURE SIGNAL 2-WAY SWITCH 1.5 V. A B T CAL.A UNIT MAGNETIC JL __ A PICK-UP I " I-EXT.SYN. AMPLI FIER DUAL-BEAM CATHODE RAY OSCILLOSCOPE Figure 9. Schematic Wiring Diagram of the Oscilloscope.

-nIFigure 10. Primary Injection Valve Opening Signal as Indicated on the Oscilloscope (the lower trace )

-18and Figure 10 (the bottom trace) shows the signal of the valve opening on the oscilloscope screen. Ho Ignition Indicator A quartz window was built in the cylinder head (Figure 5), through which the light from the ignition was transmitted and fell on the selenium face of a self-generating photoelectric cell. The electric current from the cell was applied to the B channel of the oscilloscope. Figures 5, 9, 11 and 15 show the quartz window, the oscilloscope circuit, the photocell housing, and the ignition trace respectively.

-19SELENIUM PHOTOELECTRIC - CELL Figure 11. Photoelectric Cell Mounting. ~g/ P

III. THE COMBUSTION PROCESS Knowledge of the stages through which a heterogeneous mixture of air and fuel passes before ignition starts is necessary for the rational design of any heat engine in general, and of high speed compression ignition engines in particular, where the small fraction of a second can seriously affect the performance of the engine. For discussion purposes, the time elapsed before ignition (delay period) is often divided into two components: physical and chemical. The physical component is the time during which atomization, mixing and vaporization take place, and the chemical component is that time for chemical reactions. Although the actual relative magnitudes of these two components are not known, yet, Boerlage and Broeze(13) have stated that for fuels of normal volatility, the chemical character governs the total ignition period, showing that the physical delay is short. Fuel injected through a nozzle into a combustion chamber is believed( ) to pass through the following stages: The fuel leaves the nozzle orifices as a ligament or sheet then breaks down into different size droplets. Appreciable heat transfer from the air present in the combustion chamber to the fuel occurs only after the ligament has broken up into droplets. This is due to the appreciable increase of surface area of the fuel that is exposed to the air. As heat transfer takes place, the droplets heat up (or possibly cool down, depending upon ambient air conditions and initial fuel temperature) and at the same time lose part of their mass by vaporization and diffusion into the air, with both heat and -20

-21mass transfer being markedly affected by droplet size and velocity relative to the air. At the same time, the droplets are being slowed down relative to the air by aerodynamic drag forces. After a certain time has elapsed, each droplet tends to approach the equilibrium temperature equal to the wet-bulb temperature corresponding to the conditions present at that moment. The larger droplets are slower in attaining equilibrium conditions; but, although they have essentially the same initial speed as the smaller ones, they are slowed down relative to the air at a lesser rate, due to its larger momentum, and they move along with the air ahead of the smaller ones that were injected at the same instant. The smaller drops, however, give away their mass and completely vaporize faster and travel a shorter distance through the combustion chamber than the larger droplets. A cloud of vapor due to the smaller droplets is thus rapidly formed and moves along with the air. The mass of vapor given away by the incoming larger droplets is added to this vapor cloud. Somewhere in the combustion chamber a combustible mixture of air and fuel vapor is formed and is ready for ignition at that point. In the absence of outside means of ignition, two kinds of reactions may take place simultaneously, a simple molecular reaction(5) and a chain process. The rate of molecular reaction is much larger than that of the chain reactions in some cases, and vice versa in other cases. For fuels of interest, high hydrocarbons, it is believed that the reaction is of the kind suggested by Semenov(15) "degenerate branching."

-22Since some reactions may take place during the liquid phase of the fuel the chemical portion of the ignition delay period probably overlaps the physical portion. The determination of the chemical delay depends upon understanding the mechanism of oxidation of hydrocarbons which will be discussed in the following chapter.

IV. CHEMICAL KINETICS OF OXIDATION OF HYDROCARBONS'The work on the chemical kinetics of reactions shows overwhelming evidence that most of the chemical reactions of combustion occur in a series of steps involving highly unstable species, such as free atoms and radicals. The oxidation of hydrocarbons and other organic combustibles is not completely understood, but it is known to be a chain reaction. Already the earliest theory of simultaneous explosion assumed that heat should be transfered until the unburnt layer reaches its spontaneous ignition temperature. Attractive though this theory is, its falseness is shown easily by the fact that according to it, combustion velocity should tend toward infinity with rising pre-flame temperature. But then, even for actual selfignition processes occurring under condition of short induction periods (ignition in Diesel engines), the original static conception of a spontaneous ignition temperature had proven to be inadequate; no wonder it falls even shorter of being useful in this more complicated and highly dynamic process. The oxidation of hydrocarbons frequently show an induction period, followed by very rapid reaction. In the case of methane it has been found() that traces of formaldehyde are formed in the induction period and the addition of formaldehyde shortens or eliminates the period. Thus a more dynamic concept of hypothetical character, very simplified, might start from the active particles. -23

-24Todes(17) has demonstrated that the rate of energy release, on a purely thermal basis, rises sharply with time after the first few per cent of the reaction have taken place. With all paraffins and olefins from propylene upward, cool flames occur followed by hot flames. This type of two-stage ignition is characterized with its two separate induction periods T1 and T2. The induction period T1 is from the beginning of the reaction to the appearance of cool flames; and T2 is the period from the appearance of the cool flames to the onset of violent explosion. The cool flames usually reveal peroxides and aldehydes on analysis. The emitter in these flames has been found to(18) be electronically excited formaldehydes. The temperature and pressure limits for the occurrence of cool flames, and of explosions, have been studied carefully by Townend and his co-workers(l9); for all of the hydrocarbons the temperature limits for the cool flames are about 280 to 410~C (536 to 770~F). Some of the usual features of this kind of reaction are explained by Semenov's(l5) hypothesis of "degenerate branching chains," which was put forward primarily to interpret the long induction periods found in the reaction. The chain branching actually occurs and is indicated by the fact that the reactions accelerate without any rise in temperature. Because of the complexity and hetrogeneity of the reactants in compression ignition engines the plausible mechanism, by Walsh(2), for the oxidation of a straight-chain hydrocarbon RCH2CR3 will be considered to explain the chemical kinetics of the combustion. The mechanism may be represented by the following scheme:

-25RCH2CH3 + 02 - RCHCH3 + HO (4-1) RCHCH3 + 02 > R(CH3)CHOO (4-2) R(C3H)CHOO + RCH2CH3- R(CH3)CHOOH + RCHCH3 (4-3) rc-)c R(CH3)CO + H20 (4-4) R(CH3)CHOOH - - R + CH3CHO + OH* (4-5) R CH: + 02 -- R CH0OO [R'CH2 = R] (4-6) R CH2o00 ---— RCHO + OR (4-7) R CHO- ---—.R' H + CO (4-8) According to this mechanism, the hydroperoxide R(CH3)CHOOH is an important intermediate, and is responsible for the formation of the aldehydes (CH3CHO). The radical R produced in reaction (4-5) can undergo a further series of reactions (4-6), (4-7) and (4-8), similar to (4-2) to (4-5), until all the C-C bonds are severed. Several features of this reaction scheme may now be discussed. According to the reaction (4-1), the oxygen attacks the hydrocarbon RCH2CH3 not at the end of the chain but at the tertiary 1 (7) carbon atom (-CH)'. In a straight-chain hydrocarbon the oxygen atoms. At temperatures between 300 to 4000~C [572 to 7520F] it is supposed that the decomposition of the secondary radical, R(CH3)CHOO, * This event is rare due to high energy required. ** This step may be regarded as degenerate branching. *** The most probable point of attack is at a tertiary carbon atom (-CH), and a secondary carbon atom (-CH2) is preferred over a primary carbon atom (-CH3); the probabilities of attack are 33'3:1 respectively at low temperatures corresponding to cool flame range [ref. 3, p. 172].

is unimportant, the decomposition via the hydroperoxide, R(CH3)CHOOH being dominant and the induction period is shorter the higher the temperature. As the temperature is raised the decomposition of the secondary radical becomes relatively more important, and that of the hydroperoxide molecule less. The fact that the decomposition of the molecule can be a branching chain process (reaction 4-5) explains the fact that the temperature coefficient of the rate is often found to be negative* in the range from 400 to 450~C [752 to 842~F]. At still higher temperatures the rate of the radical decomposition may have increased so much that the thermal explosions can take place. This scheme of reactions therefore represents a specific mechanism for the degenerate branching postulated by Semenov; the role of the intermediate is played by R(CH3)CHOOH, which can give rise to branching (reaction 4-5) but which can also decompose without the occurrence of branching (reaction 4-4). A. Rates of Chain Propagation and Termination In the liquid phase, the diffusion of free radicals is difficult and linear termination of chains at the wall, as in the gas reactions, is not expected. The most natural termination is by recombination of radicals R(CH3)CHOO and RCHCH.(15) The chain termination in oxidation is of quadratic nature. When the oxygen pressure is high enough, termination occurs practically exclusively by recombination of the R(CH3)CHOO radicals. Let no be the rate of initiation, k2, k3 the rate constants of steps (4-2) and (4-3), k3i the rate constant for recombination of R(CH3)CHOO radicals. With the steady state assumption, the rate W of oxidation is: At this range the time of reaction increases as the temperature increases.

-27k3 W = -k [RCH2CH5] fno k The ratio - depends on the nature of the hydrocarbons. The strikkI ing feature that the pre-exponential factors, of k's, are 5 to 7 orders of magnitude smaller than the collision factors. B. Chain Initiation and Degenerate Branching The characteristic feature of both gas and liquid phase oxidation of hydrocarbons is the auto-acceleration of the reaction. This is quite natural since hydroperoxides accumulate during the liquid phase oxidation of hydrocarbons. But peroxide compounds have the ability to initiate the process. In this sense, liquid phase oxidation of hydrocarbons is a process with degenerate chain branching and the branching agents are the hydroperoxides. In the general case, the expression for the oxidation rate has the form: W =, [RCH2CH3] /k [R(CH:)CHOOH] + k [R(CH)CHOO]2 k' may be an effective constant containing a constant solvent concentration. Bateman(21) has shown that this relation represents adequately the variation of W with [R(CH3)CHOOH] for a number of hydrocarbons, in a very wide range of hydroperoxide concentrations. Bateman has also measured the bimolecular rate constants for hydroperoxide decomposition in a variety of cases. In the case of ethyllinoleate k = 1.6 x 10t10 exp(-26000/RT) cm5/sec.

-28The most likely chain initiation step in the absence of peroxides (i.e., in the very early stages of the process) is the reaction (4-1). The reaction rate can be written as W = kl[RCH2CH3][02] = f x 1010 exp[-(qcr47000)/RT][RCH2CH 3][02] where f is a steric factor. for olefin qC = 77 k.cal. for branched paraffin qC = 89 k.cal. tertiary C-H bond C-H for straight chain paraffin qCE = 94 k.cal. secondary C-H bond. C. The Induction Period The rate Wo largely determines the length of the induction period. In order to determine the latter, it is necessary to know the kinetic equation of the oxidation process. The systems of differential equations describing the kinetics of the initial stages of the oxidation process, as long as the decomposition of hydrocarbons can be neglected, can be written as follows: d[RCHtC] = - k2[RCHCH3][O2] + k3[R(CH3)CHOO][RCH2CH3] + kl[R(CH3)CHOOH] (4-9) d[R(CH3)CHOO] - k[RCHCH3[12] - k3[R(CH3)CHOO][RCTCHI3 dt - k3.[R(CH3 )C00] (0-10) d [ R ( CH)CHOOH] =k[R(CH)CHO][RC2C~3] (4-11) This system can be reduced to (Appendix IV): 0. d _ - (4-12) T = 6'I-r + (1/2 - W')(l - e-2TI (4-12) The induction period will be defined as the time required to build up a concentration of hydroperoxide equal to 10-4 % (the threshold of analytical

-W29detection) which is equivalent to T =0.1 and(15) 0.1 0.1 din., - - rj. Cosh Wo 0.1 o ~ + (1/2 - Wo)(l - e-2i) o o~ 1000 r = 0.1 For branched paraffins Semenov gave the following values Wo = 10-8 = = 16.8 for induction period T 64.4 for reaction period Tr = 3.8 (27) Emperical equations by t6gener for n-heptane are: T1 = 8.1 x 10o2 p-66 e1500/ T2 = 0.5 p-1.82 e-1400/T Ti, T2 are induction periods of cool and hot flames respectively and p and T are in atmospheres and ~K of the conditions at the end of compression. D. Effect of Vitiation The term vitiation here will be applied to the air which contains additional gas that is neither fuel nor oxygen. For example, air containing a diluent such as nitrogen, argon or contaminated by the products of a previous combustion process within it is vitiated,. The presence of diluent gases frequently plays a very important role in the nature and course of the chemical reactions involved.

-30Dixon(22) found in his early work that within the range of delays 0.5 to 3 seconds that: T x po = constant where Po is the partial pressure of oxygen and T is the delay period. Mullins(23) found in the case of kerosene the relation: a2 - 101 exp 24000 T where a is an oxygen index and T is ~K. The effect of vitiation on the adiabatic flame temperature of a stoichiometric kerosene-air mixture is very great; it falls by approximately 700C(23) for each one per cent reduction in the oxygen concentration of the air. At temperatures below 500~C and particularly at subatmospheric pressures vitiation influences largely the course of homogeneous reactions. At higher pressures and temperatures (above 800~C) the reaction rates are usually reduced. These effects are due to: a. The change in the thermal properties of the mixture. b. Inhibition action of some of the components at certain temperatures and pressures. c. Change in the chemical reaction course, simply the rate of reaction constant. d. Change in the reaction mechanism. R. E. Miller(24) gave the following equation: T a.88 x 10-13 32400 (8.5 C' + 1) 4.exp T C1 is the fractional concentration by volume of water vapor and carbon dioxide. a is an oxygen index equal to oxygen/air ratio by volume.

-31For pure air T a1- 4.88 x 1o12 exp 2400 exp T That means that with vitiation the delay period increases to (8.5 C'+l) fold which is equal to two fold approximately under conditions of interest. It is believed that this increase in the delay period occurs mostly in the preflame reaction period i.e., T1,.

V. APPLICATION OF THE THEORY It was shown from the theoretical analysis that if it is desired to burn hydrocarbon fuel quickly it is necessary to establish at least the minimum possible quantity of radicals that suffices to bring about quick reaction. This necessitates introducing some of the fuel, to form a suitable F/A, into the engine cylinder at a certain spot and time to allow the fuel to undergo a chain process which leads to cool flame reaction where the radical concentration is sufficient to accelerate the main combustion. The formation of this concentration should occur just before the main fuel is injected at such a time as to maintain the point of the maximum pressure rise inside the cylinder at about 150A.T.C.in order to realize the maximum availability of the chemical energy of the fuel. An energy cell combustion chamber engine was chosen. The primary part of the fuel was injected into the energy cell at low pressure to form, locally, a rich mixture of fuel and air. Since the energy cell is at a temperature, on the average, corresponding to the cool flame range, thus the formation of the radicals can be secured. Should part of the fuel diffuse into the main combustion chamber, it will help in raising the combustion chamber efficiency and improve the air utilization and increase the maximum output of the engine i.e., decreased the specific weight of the engine. -52

VI. OPERATING CONDITIONS AND TEST PROCEDURE The engine was started and run for a period of time to warm up to a predetermined condition as expressed by cooling water and lubricating oil sump temperatures. The points on the b.s.f.c. versus P.F./T.F.% curves were deliberately obtained at P.F./T.F.% in a random order and this scatter of adjacent points about the mean curves gives some indication of the reproducibility. The following series of experiments were carried out: Series I. The purpose of which was to determine the performance of the engine after modification without P.F. Series II. To determine the most favorable time of injecting the primary fuel into the energy cell covering the range from 45~ A.T.C. during the suction stroke to 60~ B.T.C. during the compression stroke. This range was limited by those timings at which excessive brake specific fuel consumption occurred. These series were conducted at a constant engine speed of 1600 r.p.m. and 54.3 lb/in2 b.m.e.p. for safety consideration which will be mentioned later. Series III. Its purpose was to investigate the effect of injection pressure of the primary fuel on the engine performance. The range of pressure was from 600 to 1400 lb/in2 in 200 lb/in2 increments. The test was carried out for the above chosen load and speed at the optimum primary fuel injection timing. The pressure range was limited by those pressures at which excessive brake specific fuel consumption occurred. * This modification includes provision for pressure pick-up installation, the quartz window, modifying the energy cell as shown in Figure 5 and driving the primary injection pump. -33

-34Series IV. To show the effect of cooling water temperature on the engine performance and to determine the optimum operating temperature. The test was carried out at constant speed for the optimum performance as determined by series I to III and at constant rack position of primary fuel injection pump to supply the P.F./T.F.% of about 5% which produce an economical b.s.f.c. The range of temperature was from 1150 to 180~F limited by the occurrance of excessive b.s.f.c. Series V. To determine the physicochemical delay of the combustion at variable speeds. This series covered the range from 800 r.p.m., the idling speed, to 2000 r.p.m. The maximum speed of 2000 r.p.m. was asigned for safety consideration. The P.F./T.F.% was determined as the minimum quantity that the primary injection pump could supply and still produce ignition at idling speed. This amounted to about 15.8of the total charge. Series VI. With the primary injection timing, and pressure, and cooling water temperature set at the optimum conditions (maximum economy), the effect of changing the main fuel injection timing was investigated. Timing was altered by changing the clearance between the cam and the injection pump plunger follower. Injection at 9~ B.T.C. and 14~ B.T.C. were tested and compared with the standard 190 and a series of runs carried out for each timing. Series VII. To show the effect of adding cumene hydroperoxide to both primary and main fuel individually and simultaneously. A mixture of 1% by volume of cumene hydroperoxide in diesel fuel was used. Series VIII. To find the effect of the energy cell throat cross sectional area on the performance. Two throat diameters were investigated. The original diameter was 0.1495 in.(A = 0.017554 in2) and the second

-35alternative was 0.196 in. (A = 0.030171 in2). No larger diameter needed to be examined because of the resulting increase in b.s.f.c. Smaller sizes have yet to be investigated. The following readings were taken for each run: 1. Lubricating oil temperature in the crank case sump = T oiF. 2. Cooling water temperature at the water pump inlet = TW F. 3. Exhaust gas temperature after it leaves the cylinder head exh. F 4. Time for consumption of 1/8 lb of main fuel in minutes = tm minute. 5. Time for consumption of 1/16 lb of primary fuel in minutes tp minute. 6. Number of revolutions of the crank shaft during the time recorded under 4 = Nm. 7. Brake torque F lb.ft. 8. Primary fuel injection timing in degrees before or after T.D.C. = p deg. 9. Beginning of combustion as indicated by the start of sudden pressure rise = Gi deg. 10. Point of maximum pressure 3 Qax deg. 11. The ratio of sudden pressure rise to compression pressure. 12. Pictorial records of representative runs showing the following traces: a. Pressure-time diagram for the cycle. b. Primary injection valve opening time. c. Optical intensity of flame in the cylinder. The test results are given in the appendix in Tables I to XLIII. Since the engine was designed to run under normal conditions, and to avoid undue damage, the following limits were employed:

Exhaust temperature not to exceed 1100~F. Maximum pressure inside the cylinder not to exceed 1200 lb/in. According to these limitations the following engine conditions were chosen for the majority of runs: Load (b.m.e.p.) = 54.5 lb/in2 Speed = 1600 r.p.m. + 3% Cooling water temperature = 140~F + 2~ Lubricating oil temperature in the engine sump = 160~F + 2~ The engine was inspected at the end of the tests and found in satisfactory condition.

VII. DISCUSSION OF EXPERIMENTAL RESULTS Series I. Performance Test of the Engine After Modification This series of runs was carried out to determine the performance of the engine after modification and duplicate runs were made from time to time to assure the consistency of the engine conditions. This test was carried out at a constant engine speed of 1600 r.p.m. and covered the load range together with the maximum over-load employed. These results are shown in Table I and Figure 12 which are typical of such engines. Figure 13 shows the P-t diagrams of this test. Series II. Runs at Variable Primary Injection Timing Under constant engine conditions, series of runs were carried out at each timing. The primary fuel consumption to the total fuel consumption was changed from zero to about forty per cent. The chosen load and speed for this series were 54.3 lb/in2 b.m.e.p. and 1600 r.p.m. respectively. The P.F. injection pressure was 800 lb/in2. Figure 14 shows the relation between P.F./T.F.% and brake specific fuel consumption, delay period in degrees crank angles, T, and exhaust gas temperature for P.F. injection occurred at 45~ B.T.C. during the compression stroke, 5~ B.T.C. and 60~ B.T.C. during the exhaust stroke. The brake specific fuel consumption decreases to a minimum as the P.F./T.F.% increases, then it begins to increase to a maximum value, usually higher than the value corresponding to non-primary

N= CONSTANT s 1600 r.p.m. WITHOUT P.F. INJECTION 800 700 f^ x 500 I 70 0- 400 C) W 60 C-) o 40 30 40 _) 30 C: 1.00 10 a. 0.9 0.8, 0.7. 0.6 0.5 -~ — 10 20 30 40 50 60 70 80 B.M.E.P Lb/in2 Figure 12. Engine Performance After Modification. (Series I).

-39i:ri i Figure 13. Pictorial Traces of Pressure-Time Diagrams (Series I). P.F./T.F.% = O Run No. B.M.E.P. Run No. B.M.E.P. a 1 18.1 d 4 65.1 b 2 36.2 e 5 76 c 3 54.3

.-~~~~~~~~~~4o--- --- --- - X ~#/.. 600 " " -- --- 7 450 " (com) N AsN1600 rp.m. B.M.E.P=54.3Lb/in 800 100QQ^""ry XX __-X --— X ~. 700 50 C) 40 ir 1- 30 -- 20 |L 20 1 0.70 --- -- -- --- -- — ^ —- --- --- --- -- -- 10 ~~~~~~~~~~~-C 0' -r 0.70.00 ~ ~ ~ ~~~. 0.50 10 20 30 40 50 60 P.F/ T. F% / Figure 14. Effect of P.F. Injection Timing Upon Engine Pe'f ormance. (Series II)

-41Figure 15. Pictorial Traces of Pressure-Time Diagrams at Various P.F./T.F.% (Series II) P.F. Injection Begins 60~ B.T.C. [exhaust] Run No. P.F./T.F. % Run No. P.F./T.F.% a 1 0 f 184 26.2 b 180 6.22 g 185 36.8 c 181 9.62 h 186 48.5 d 182 14.92 i 187 56 e 183 23.2 j 188

Figure 15. Pictorial Traces of Pressure-Time Diagrams at Various P.F./T.F.% (Series II), Lower Traces Show Flame Intensity.

-43fuel injection, and then decreases again. From this point on b.s.f.c. appeared to continually increase. The delay period decreases to a minimum as the P.F./T.F.% increases, and then increases slightly. The delay period decreases first with an increasing rate, then the rate gradually decreases to zero at the inflection point (minimum delay), from this point on the delay period begins to increase. Since the rate of decrease of delay period is very small at the very low P.F./T.F.%, while there is a similtaneous remarkable change in the pressure-time curve, a time characteristic value T defined as follows is introduced. T= deg. crank angle elapsed during sudden pressure rise max pressure-comp.press. comp. press. oi / Pmax-Pcomp max i comp co amp The time characteristic T is inversely proportional to the reaction rate. It shows the effect of accelerating the reaction rate. The T curves have the general form of the delay period but the rate of decrease of T is magnified at the first part of the curve. The exhaust gas temperature curve follows approximately the shape of the b.s.f.c. curve. By injecting part of the fuel into the energy cell early in the cycle, it is exposed to high temperature and suffers preflame reactions in the T1 regime (cool flames) where suitable concentration of hydroperoxides are ready prepared, at the time of the main injection, to trigger the main fuel combustion with reduced delay.

-44Since the rate of formation of intermediates is a function of fuel concentration (Equation 4-11), this explains the first portion of the curves in Figure 14, i.e., as P.F./T.F.% increases (the concentration of P.F./A increases), the possibility of higher concentrations of intermediate products is evident. This shortens the delay* and most of the energy released from the main fuel is attained earlier in the cycle, i.e., at the highest possible temperature or in other words the highest possible availability. The accompanying effect is higher efficiency and lower exhaust gas temperature due to larger expansion ratio because of earlier maximum pressure rise, faster reaction and shorter afterburning as shown in Figure 15a and 15b. (Bottom traces) As the P.F./T.F.% increases higher than the economical ratio three possibilities may exist: 1. The combustion rate increases to a point where maximum pressure occurs very early resulting in increased negative work on the piston during the compression stroke. 2. Some of the primary fuel burns in the energy cell early in the cycle at low level of availability. 3. The temperature of the energy cell increases and two other possibilities may arise: a. Part of the primary fuel evaporates which changes the reaction mechanism. The diffusion of radicals and their termination at the wall surface will increase (p. 26). * Semenov has estimated the induction period of branched paraffins as 1/4 the reaction period of stoichiometric mixtures with oxygen at temperature of 4000K and atmospheric pressures.

-45b. The cell temperature achieves the negative coefficient range ( 410~C, p. 24 ), that is the reaction rate decreases as shown in the humped portion of T curves (Figure 14). The coincidence of the point of minimum brake specific fuel consumption with the point of minimum T supports this reasoning. Further increase in P.F./T.F.% can cause decrease in the temperature of the energy cell due to the latent heat absorbed by the larger quantity of P.F. which can overcome part of the effect of the hot cell. The second minimum of b.s.f.c. is limited by the efficiency of fuel distributing and mixing in the combustion chamber due to its design and geometry. The optimum timing of the P.F. injection was found to be at 5~ B.T.C. during the exhaust stroke. The brake specific fuel consumption increases for P.F. injection on either sides of this point. When the primary fuel is injected too early during the exhaust stroke, it is probable that part of the P.F. escapes with the exhaust gas. On the other hand with P.F. injection during the compression stroke, the short period between the P.F. and the M.F. injections will not be sufficient for the production of the minimum required quantity of radicals in the preflame reaction for accelerating the main combustion. Injection of P.F. in the exhaust stroke favors the engine performance since part of the P.F. may diffuse to the main chamber and some active intermediate products from the previous cycle may act as reacting centers to accelerate the reaction.

-46Series III. Variable Primary Fuel Injection Pressures At low injection pressure, the fuel droplets are large and the surface to volume ratio is small. Since the reaction rate is a function of surface, then the T is expected to be larger at the low injection pressure as shown in Figure 16. Moreover the penetration of the P.F. will be less i.e., less exposed to oxygen, as will also be the active radicals, which increases the tendency to higher b.s.f.c. At higher P.F. injection pressure the atomization is better and the penetration is deeper. Higher atomization increases the droplets surface to volume ratio resulting in higher rate of evaporation was well as a higher rate of reaction. If the rate of vaporization is high, the oxidation mechanism will differ and the rate of termination of the active radicals at the E.C. wall surface will increase. Deeper penetration will increase the percentage of fuel injected through the E.C. throat and to the wall surface. The part of the fuel which will pass through the throat will be exposed to relatively low temperature resulting in retardation of pre-flame reaction and radical concentration. The part which will diffuse to the walls will suffer the termination of its active radicals. Both actions, greater atomization and penetration, will probably act to retard the combustion. Figure 16 shows this trend, higher T and Texh are indications of slow combustion and longer afterburning. Between the two extremes of the P.F. injection pressures, there is an optimum value. As far as brake specific fuel consumption is concerned, the optimum injection pressure was found to be about

-47O PE INJECTION PRESSURE =800 Ib/in. *,,,,,, 1400 t O, H I, 1200. X oa e II = 1000,, A m*, = 600 cc N s 1600 c pm. 2 B.M.E.P. = 54.3 Lb/ n j'; R1 PF INJECTION BEGINS 5~B.T.C.(Exh) 800 3.3- 700: i ~ — - - -- -- - -- (0 600 50 IO 40 3 0 020 i0 - i10~~~~~~~~~~~~~~~0'o 0 F./T 20F ~/ Figure 6. Effect of P.F. Injection Pressure Upn 0Performce. (Series III). IJ 0.50 0 10 20 30 40 50 60 70 RF./T.F % Performance. (Series I II).

800 lb/in2. For minimum T, injection pressure was found to be 1000 lb/in2. Series IV. Runs at Variable Cooling Water Temperature At constant engine conditions, one run was carried out at each cooling water temperature. Figure 17 shows the b.s.f.c., -1, T, and T versus cooling water temperature for 54.3 b.m.e.p; 50 B.T.C. exh (exh.), 800 lb/in2 for primary fuel injection timing and pressure respectively. As the cooling water temperature increases the b.s.f.c. decreases to a minimum at 142~F where it begins to increase. T decreases with a decreasing rate as the temperature increases. As the cooling water temperature increases, the engine runs hotter on the average and shorter delay is to be expected, due to faster reaction rate and shorter physical delay. The increase of b.s.f.c. after 142~F is due to the following reasons: a. The earlier the ignition, the higher is the negative work on the piston during the compression stroke. b. The higher the temperature, the greater the possibility for the energy cell to achieve the negative coefficient temperature range, which decreases the rate of reaction. In support of this, is that T decreases with a decreased rate. c. The higher the temperature, the faster is the vaporization of the P.F., which may affect the kinetics of reaction since the mechanism in the liquid phase is different from that in the vapor or gaseous phase. ) Figure 18 shows the P-t diagrmas of this series.

-49N = CONSTANT 1600 RRM. B.M.E.P= 54.3 Lb/in2 P.F/T.F. %~ 5% P.F. INJECTION BEGINS AT 5~ B.T.C. (Exh) P.E PRESSUIE = 00 L)/in 800~ 40 a: w 30 CC 20 a. 20 r 0.56 W. 0 ad LU -o 0.54 110 120 130 140 150 160 170 180 Tc D F...Figure 17. Effect of Cooling Water Temperature Upon Engine Perormance. (Series W). Engine Performance. (Series IV).

-50Figure 18. Pictorial Traces of Pressure-Time Diagrams at Various Cooling Water Temperature. (Series IV) P.F. Injection Begins 50 B.T.C. [exhaust] P.F./T.F.% = 5% Run No. T. OF Run No. T. W. "~~:~~-,iilli i i1!~~~~~~~~~~~ —~ — x~~~ 1~ ~~~~~~~~ -~=I:-~-!! i-ii~!1!i iiiill?i" i11ii- i~ 5 66 158 ~ 569 115

-51Series V. Runs at Variable Speed At constant engine conditions and the optimum performance as determined by the previous series of tests the engine was run at different speeds to determine the delay period. The injection pumps racks were locked to maintain approximately constant quantity of fuel injection per cycle. This assumption neglects the variation of volumetric efficiency of the pumps with the engine speed variation. The P.F./T.F.% was determined as the minimum quantity that the primary injection pump could supply and still produce ignition at the idling speed which amounted to 15.8. The delay period decreases linearly as the speed increases and the rate of the decrease was the same in both cases, with and without P.F. injection. The decrease in the delay period due to the rise in speed from 950 to 2000 r.p.m. was, in either case, about 1.5 milliseconds which is probably due to higher air swirl and higher engine temperature. Figure 19 and Tables XXX and XXXI show the result of this test. Figure 20 shows the P-t diagrams at various speeds, with P.F./T.F.% - 15.8 (20a to 20h) and without primary fuel injection (20i to 20p). At 2000 r.p.m. without P.F., the combustion was almost at constant pressure (Figure 20m) and the end of the combustion was at 30~ A.T.C., while with P.F. injection at the same speed and load, the combustion was almost at constant volume (Figure 20c) and the maximum pressure occurred at 15~ A.T.C. The test results show that (a) for a delay period of 2.8 milliseconds the engine speed was 1050 r.p.m. with P.F. and 1800 r.p.m. without P.F., and (b) for the same speed of 1800 r.p.m. the delay period with P.F. was 57.1% of that without P.F.

-52P.F/T.F. % = 15.8 1000 ) P.F./T.F. % = 0.0 PF.INJECTION BEGINS AT5~ BT.C(Ext.) 900 P F PRESSURE =800 Lb/in / 800 XAXB.M..P 54.3 Lb/in2 x 700 600 1 120 - 500 -: 4.0 - 3.6 3.2' 2.8 2.4 0 0 n' 2.0 w 1.6 w 1.2 800 1000 1200 1400 1600 1800 2000 ENGINE SPEED r.p.m. Figure 19. Effect of Engine Speed Upon Delay Period and Exhaust Gas Temperature. (Series V).

Figure 20. Pictorial Traces of Pressure-Time Diagrams at Variable Engine Speed. (Series V) P.F. Injection Begins 5~ B.T.C. [exhaust] Constant Fuel Injection Per Cycle Run No. N P.F./T.F. Run No. N P.F./T.F. a 370 1775 15.8% i 378 1625 0. 0% b 571 1915 15.8 j 579 1760 0.0 c 372 2000 15.8 k 380 1860 0.0 d 373 1700 15.8 1 381 1940 0.0 e 374 1390 15.8 m 382 2040 0.0 f 375 1150 15.8 n 385 1480 0.0 g 376 950 15.8 o 384 1180 0.0 h 377 1640 15.8 p 385 850. 0

Imi P — (D' ro 0 ~~~~~~~~~~~~~~~~~~~~~~~-~i-Jo~~~===I"~ ~ I 0 F+i~iiiiii!??;D - "I''I I 1 I N 0!

-55Figure 20. Contunued,

-56. The decrease of the delay period and the increase of the reaction rate (combustion) that occurred in the test could permit a larger increase in speed of rotation of the engine than that actually used in this case (limited to engine safety condition) and it has been demonstrated that P.F. injection early in the cycle is one means of achieving the pre-flame reactions necessary for this. Series VI. Runs at Different Main Fuel Injection Timing At constant optimum engine conditions, series of runs at each main fuel injection time were carried out. The injection timing was altered by changing the clearance between the cam and the plunger follower. Although the acceleration behavior of the plunger is changed by the alteration of the clearance, because of the small range of clearance change (0.030"), this effect can be neglected. Figure 21, to 24 and Tables X, XXXII to XL show the results of this series. For M.F. injection retarded to 9~ B.T.C. the engine was not able to generate the 54.3 b.m.e.p. without P.F. injection, but as soon as a very small percentage of P.F. was injected it was easy for the engine to generate the load. This is due to earlier combustion and maximum pressure rise accompanied by an earlier end of the afterburning as indicated by the decrease of exhaust gas temperature. With P.F. injection the engine runs very smooth and the delay period was almost zero. Figure 25 shows the P-t diagrams for M.F. injection at 9~ B.T.C. At 14~ B.T.C., the engine ran smooth and the delay period was very short. The engine was able to generate at this timing, with P.F. injection, 17.85% overload with 12% decrease in the b.s.f.c. and

-57_ -M.F INJECTION BEGINS AT 190 B.T.C. 900 900 A-,,,,,, 140, 800 LL -— P.E3Lx -" " 90 " 5~^800, 700 x 600 50 40 0 3: X' I \ 0 U 00 co — "x-~-x —- o0 0n 0 ILL__________ ^ ^ I^~~~X \ IO IIII I I 10.20 30 40 50 60 Figure 21. Effect o Main Fuel Injection 54.3 Lb/in Upon 0.50Engine Performance. (Series VI). ai I I I I I I I I I ) N ~ 1600 rp.m. 10 20 30 40 50 60 RF /T.F% Figure 21. Effect of Main Fuel Injection Timing Upon Engine Performance. (Series VI).

-58M.F INJECTION BEGINS 19~ B.T.C,(Ext). XP. " 5~14 0.9 \, _ BM.E.P 18.2 Lb/in. 0.8 m _ 0.7 0.6 0.5 BM.E.P.5436.23 Lb/in. PAI600 rprm. 0 10 20 30 40 50 60 70 PF/T.F % Figure 22. Effect of M.F. Injection Timing Upon B.S.F.C. (Series VI).

-590 WITHOUT PRF RF. INJECTION BEGINS 5~B.TC.(Exh.) M.F INJECTION,, 190 1000 O WITH P.F. LL N =10oo r.p.m. --— l —-- - -— ^ ^ ^.--- 1.-0"'~- ~-""'"'""-' 600 x a 30 I-MF- - - - -- - - - 400 i'^t 0 0___-_ i: WITHOUT P.F t>50. I: o I0 1 0 aI. 0.07. I 0.05 0.03 0.01 10 Li. C 1.00 30 0L 0.9 jO..8 M 0.7 0.6 0.5 10 20 30 40 50 60 70 80 B.M.E.P, Lb./in' Figure 23. Effeet of Primary Fuel Injection Upon Optimnum Engine Performance. (Series VI).

-600-WITHOUT F 1000 * WITH P.F. io o 800 o,' i -F 600 I —-^^^^^ —-------— 600 FH |n 400 MJ 0 20' WITHOUT PF. T>20C ---:: -----— 0 1 0 I0 - - - --- --- - IN — - -- - - - 0I 4 BT.(fl 0.~_~^~~ 630 20 w a. _J 0.05 -- O 0.03 LL. 0.01 20 L3 10'". a: 1.00 I -B.M.E IP, NJECTION BEGINS 14 BC.(Ext) -j E t of F.u ectin Optimum Engine Performance. (Series VI). LL N 1600 r.p.m. a 0.7 0.6 0 - 10 20 30 40 50 60 70 80 B.M.E.P., Lb/in2 Figure 24. Effect of Primary Fuel Injection Upon Optimum Engine Performance. (Series VI),

Figure 25. Pictorial Traces of Pressure-Time Diagrams (Series VI) M.F. Injection Begins 9~ B.T.C. P.F. Injection Begins 5 ~ B.T.C. [exhaust] B.M.E.P. = 54*3 lb/in2 Run No. P.F./T.F.% Run No. P.F./T.F.% a 386 22.4 f 391 8.75 b 387 17.15 g 392 3.34 c 388 15.29 h 393 28.1 d 389 13 i 394 30.4 e 390 12.65 j 395 o (B.M.E.P. 45.6 lb/in2)

i~a~~~~~-~:1::~:: i~: -62-::~~:~:j:i~i.............. -~~~~~~~~~~~~~~~~~~~~~wil-::-~~~~~~~~~~~~~~i........ "~~~~~~~w va:.~::-:~::::~~~~~ ~~~i~~~~~~j'~~~~~3i~~~~~~~::~~~~:~~~~~~~~::~~~~~~~~i:~~~~i~~~~-~~~~~~i~~~j~~~~i~~~ii....... j~~~i~~~~:~ ~ ~ B~~i~'''i~Bi'~~:~''' -:::,::::.......... I ~~~~~~:~,~~:~~~::~:~~:~j~~::~~i~~~. ~............ il~;~~~~'~~~:~:'~~'~i~i~'~::~:~:~i~' -::-:-:;:::::::':;::::::::':::;:::::';::...................:Q::-~.~:::.:.......... ~ ~ ~ ~ ~ ~ ~ E~............ -'a::ia:~~~~~i~i-aiiiii:&;':~~~~~3 i ~........ ~~~~~~~~~~~i~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~............... ~~i:'~~~~:~~:~~~~s~~~i~~~~~~~::~~~;~~::::~~~~~:~~j, ~ ~............ L~~~~~~~~~~~~~~j~~~~~~~~~~~~~~~~~~~~~j ~ ~............... ~~~z~~~~j~~~~i~~~~~~~~~~::i~~~~~~~-.i.~~~~~~~~:::~~~~~~::;~~~~~~~~~~~:~~~~i::,............... ~~:~i:~~:~~:~i~~~~:~~~~~i:~~:~~::~~~~~~~~............:::::::::::::-:::::::::~::::::::M~:-':lk~~~~?~~~:"~~:~~~~~~:::~~~:~~:::~~~~:~~~~~:~~~~i::~..................~ ~ ~ ~~~~~~~~~~~_::::........... ~ ~ ~ ~ ~ ~:::::~I:-............ ~i~ed

-63Figure 26. Pictorial Traces of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 14~ B.T.C. P.F. Injection Begins 5~ B.T.C. [exhaust] B.M.E.P. =54.3 lb/in Run No. P.F./T.F.% Run No. P.F./T.F.% a 412 6.45 e 416 21.8 b 415 8.92 f 417 15.25 c 414 15.45 g 418 24.58 d 415 15.65 h 419 30.1

ol 0 m ~D 0" l-:

-65Figure 27. Pictorial Traces of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 14~ B.T.C. P.F./T.F.% =- Run No,. B.M.E.P. a 396 18.1 b 397 36.2 c 398 54.3 d 399 66.9

-66Figure 28. Pictorial Trace of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 140 B.T.C. P.F. Injection Begins 50 B.T.C. B.M.E.P. = 18.1 Run No. P.F./T.F.% Run No. P.F./T.F.% a 400 35.5 3 403 13.85 b 401 55 e 404 10.1 c 402 19.35

67Figure 29. Pictorial Trace of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 140 B.T.C. P.F. Injection Begins 5~ B.T.C. [exhaust] B.M.E.P. = 356.2 Run No. P.F./T.F.% Run No. P.F./T.F.% a 405 14.25 6 408 16 b 4o6 9.99 e 409 21.5 c 407 6145 f 410 27.9

-.68..~.~..~ ~. ~...~. x~..~.~.~.~.~.-.~.~! ~'~~. Figure 50. Pictorial Trace of Pressure-Time Diagrams, Maximum Loading (Series VI). M.F. Injection Begins 14~ B.T.C. P.F. Injection Begins 50 B.T.C. [exhaust] Rm No. P.F./T.F.% B.M.E.P. Run No. P.F./T.F.% B.M.E.P. a 420 7 89 74.2 e 424 16.25 77.7 b 421 3 87 69. 6 f 425 18. 6 79 6 c 422 8. 15 72. 4 g 426 19. 8 79 6 d 425 11 85 76

-69Figure 31. Pictorial Traces of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 19~ B.T.C. P.F. Injection Begins 50 B.T.C. B.M.E.P. = 18.1 lb/in2 Run No. P /T.F.% Run No. P.F./T.F. a 427 37.3 e 430 17.6 b 428 31.9 f 431 13.5 c 429 24.41 g 432 10.55

-70Figure 32. Pictorial Traces of Pressure-Time Diagrams (Series VI). M.F. Injection Begins 19~ B.T.C. P.F. Injection Begins ~o B.T.C. B.M.E.P. = 36.2 lb/in Run No. P.F./T.F.% Run No. P.F./T.F.% a 434 14.31 d 437 13.9 b 435 9.25 e 438 19.6 c 436 7.74 f 439 27.8

Figure 35. Pictorial Traces of Prs sure-Tme Diagrams^ Maximum Loading (Series VI)., @M.F Doaeti'on B'e.in. 190 B TC% P.F. Injectioli Begins 5~ B.TC. PU o. P.F./T.Fen BegBM.ns 5.P a 440 15 76 b ~4a 17@'85 78, c 4^42 7X55 82.2 d 4543 5at.15 76 9 ~~.e 444 5 72-. ^ ~:~ii~i~11~i ~ ~~,~.44 4 t4 t<4 >.444..4// / 4,,~~...>~,i i ii,! iiiii i

-726.97% decrease in the exhaust gases temperature (73~F). A decrease in the b.s.f.c. was noticed, over the whole range, when injecting the P.F., although the usual wavy curve still existed. The b.s.f.c. was lower within the range of 11 to 24% of P.F./T.F.% compared with the case of main injection at 19~ B.T.C. Figure 24 shows the performance curves and Figures 26 to 30 show the P-t diagrams of the load range. The results are given in Tables XXXIII to XXXVII. Series VII. Runs With Additive Cumene hydroperoxide is known as a fast chain initiator, then its effect in shortening the delay period is a solid proof that the ignition of diesel fuel is of chain character. A mixture of 1% by volume of cumene hydroperoxide in diesel fuel was used to investigate its effect and support the theoretical analysis. Without P.F. injection and with diesel fuel-cumene hydroperoxide mixture as M.F., the delay period was shortened (pI was 24~ as compared to 32~ in case of no additive). This result substantiates the theory given before. Table XLI shows the results and Figure 34 shows the P-t diagrams of this series. Series VIII. Runs With Variation of Energy-Cell Throat Diameter* The energy cell throat area was increased by 72%. The general b.s.f.c. was increased, but its minimum value was found to have shifted to about 25% of P.F./T.F. The engine runs smoother and the delay period d.1 = 0.1495 in., A1 = 0.01755 in.2 d2 = 0.196 in., A2 = 0.030171 in.

-73Figure 34. Pictorial Traces of Pressure-Time Diagrams, Additive Effect (Series VII) M.F. Injection Begins 190 B.T.C. P.F. Injection Begins ~ B.T.C. 3.M.E.P. = 54.5 lb/in Additive Run No. P.F./T.F.% P.F. M.F. a 445 0 - No b 446 15.1 No No c 447 12.7 Yes No d 448 15.2 Yes Yes e 449 0 - Yes f 450 12.1 No Yes

and Texh. are lower than that of the smaller throat area, but T was larger. The relatively higher T explains the smooth running conditions of the larger throat area. There is a possibility of optimum throat area corresponding to primary injection timing and pressure which needs further investigation. By increasing the throat area, the energy cell surface area increased also. It is the surface which is responsible for chain termination, that is,the larger the surface the slower the chain propagation, which results in lower rate of reaction as seen from the higher r. Figure 35 shows the performance curves, Figure 36 shows the P-t diagrams, and Table XLII shows the test results of this series of runs.

-750 HROAT DIAMETER z 0.1495 in. 800 oL %t * = o" 0.196 in.. 700 " I. o 40o_ w 30 30 -- 00 L C- 0~~~~0e 30 -10 _ ___ — __ ___.__M.F, f 19~0 o 20 w.a PF INJECTION BEGINS 5 B.T.ClExh) 0 10 20 30 40 50 60 70 RF. /T.F. % Figure 35. Effect of Energy-Cell Throat Diameter Upon Engine Performance. (Series VIII)

Figure 536 Pictorial Traces of Press e-Time Diagrams (Series VIII) Throat Diameter e 0 196 M.F. Injection Begins 19~ B T.C. P.F. Injection Begins 5 B.T.C. B M. E P = 543 lb.s/lin Run TNo P. F/T. F Rmu No. P. F/T.F. a 451 3 45 g 457 25 6 b 452 100 1 h 458 28 9 e 453 6o05 i 459 37 i 454 1 j 460 44 e 455 l6~ 6 k 461 50.4 f 465 8 65 1 462 0

- rLhnxTqi-oD *6 9~ nMEOW

VIII. GENERAL DISCUSSION Figures 37, 38, and 39 show the P-t, P-v and log P-log v diagrams respectively. The superimposed diagrams represent the fuel air standard cycle considering the cooling losses, the actual cycle without P.F. (run 3), actual cycle for minimum fuel consumption (run 190), and actual cycle for minimum delay period (run 192). The corresponding oscilloscope pictoral traces are shown in Figure 37. The standard air fuel cycle was chosen to have the same initial condition and the same maximum pressure rise and F/A equal to that of run 35 The negative work on the piston during the compression stroke of the standard cycle is smaller than the actual cycles due to the irreversibility of the compression process of the actual cycles. Due to the longer afterburning in run 3, the engine runs on the average at higher temperature, which causes the negative work to be higher in this case (afterburn for run 3 is up to 110~ A.T.C. as compared to 80~ A.T.C. in run 192). Figure 37a and 57c, the lower traces, show the flame intensity inside the cylinder. With P.F. injected in any ratio, the ignition was almost at constant volume which increases the efficiency and improves the thermodynamic cycle at any P.F./T.F.%. But also with higher P.F./T.F.% the maximum pressure rise is higher and sudden which increases the cooling losses during the combustion process. With the maximum pressure rise occurring at 22~ A.T.C. (run 190) the efficiency was maximum, but the maximum pressure and temperature were less than run 192, which favors the efficiency due to less cooling losses and dissociation. The solution of the air fuel standard cycle is shown in Appendix VI. -78

-79The photoelectric-cell was not able to detect the light of the cool flames. The beginning of the ignition (hot flames) coincided with the beginning of the sudden pressure rise. The log log diagrams (Figure 40) show that considerable reaction took place earlier than the point of sudden pressure rise and this can be explained that the cool flame reactions are taking place.

-80Figure 37. Pictorial Traces of Pressure-Time Diagrams (Lower Traces Show Flame Intensity). B.M.E.P. = 54.3 Run No. P.F./T.F. k B.S.F.C. a 3 0 29 0.567 b 190 6.64 27 0.582 c 192 20.1 17 0.595

1200 I I. RUN NO. p' P.F./T.F. % 1100 0 -- - 3 29 00-190 27 6.64 1000 X-192 17 20.1 f 900.-BM.E.P =54.3 Lb/in2 w= _ _ - 1 gC N~600 r.p.. -1 700 rt 600 i/!-7'i-c h -i600 0- 400O 200 4 I00 180 160 120 80 40 T.C. 40 80 120 160 180 CRANK ANGLES DEG. Figure 38. Pressure-Time Diagrams.

-821200 100 RUN NO. / P.F./T.F% 1100 X — ----- --------------- -0 3 29 0 1000 * 190 27 6.64 % X 192 17 20.1% 900 A FUEL-AIR STANDARD 0 CYCLE 2 n_ 800 B.M.E.P: 54.3 Lb/in'So~^~~ JL~N #s 1600 rpm.. 700 WII 500 - 400 200 300 10 20 30 40 50 60 70 80 90 100 VOLUME, in3 Figure 39. Pressure-Volume Diagrams.

-83-,ooo ~- ----- 9 8 6 10 — L 2N 100 27 6.64 r 9 lo I I NIO=t P.F./T. F.%111 192 17 20.1\) A _ STANDART AIR-FUEL CYCLE 4 - B.M.E.P 54.3 Lb/in N |I600r.p.m. 2 190 27 6.64 - x - 192 17 20.1 A - STANDART AIR-FUEL CYCLE 10 I I I -- --- I I 3 4 5 6 7 8 910 2 3 4 5 6 78910 Log.VOLUME, IN3 Figure 40. Log. Pressure-Log. Volume Diagrams for

X. SUMMARY OF RESULTS From the foregoing results it is concluded that: 1. The b.s.f.c. could be decreased by 6.25% in the entire load range; the maximum load was increased by 10.7% limited by exhaust gas temperature of 1165~Fj the delay period was decreased by 47%, and the engine speed could be raised to at least twice the designed engine speed despite the fuel injection system being designed for 1800 r.p.m. Moreover, the maximum output could be increased more than the above mentioned value by allowing the exhaust gas temperature to exceed 1165~F. The conditions under which these results were achieved were: a. M.F. injection begins at 19~ B.T.C. b. P.F. injection begins at 5~ B.T.C. during the exh. stroke. c. P.F. injection pressures is 800 lb/in2. d. Cooling water and lubricating oil temperatures are 140, 160~F respectively. e. P.F./T.F.% equals about 6%. 2. By retarding the M.F. injection the engine runs smoother, with shorter delay, and higher economy in the over load (26% decrease in b.s.f.c. at 6.45% overload at M.F. injection begins 14~ B.T.C.). When the M.F. injection begins at 9~ B.T.C., the delay was practically eliminated at P.F./T.F.% of 12.5%. 3. Means for assisting the production of high and variable speed compression ignition engines are established by shortening the delay period and accelerating the reaction rate. At 2000 r.p.m. and,8J^

-85P.F./T.F.% of 15.8, the maximum pressure rise occurred at about 15~ A.T.C., while it was at 30~ A.T.C. in case of no P.F. injection at the same speed, and the heat addition was almost at constant pressure with the expected low efficiency. The delay period at 2000 r.p.m. with P.F. injection was 1.339 millisecond as compared to 2.45 milliseconds in case of no P.F. injection. 4. Increasing the energy cell throat area by 72%, increased the b.s.f.c. by about 6.77% but the engine ran smoother and the delay period was longer. The utilization of two injection pumps and two injection valves is an additional complication or handicaps, but it is believed that this could be overcome by such a scheme as shown in Figure 41. A gear pump to compress fuel into a pressure vessel or header to supply two electrically operated injection valves, could be used. By using electrically operated injection valves, an optimum injection timing for each load and speed could be controlled and easily achieved. The possibility exists that such a scheme involves reduction in cost considerably.

-86M.F VALVE COMBUSTION CHAMBER PRESSURE VESSEL FUEL OUT FUEL IN GEAR PUMPY CELL FP F VALVE. Figure 41. Suggested Injection System.

XI. CONCLUSIONS AND RECOMMENDATIONS Conclusions The results presented above show that it is possible to control the combustion in compression ignition engines by inducing sufficiently high concentration of radicals in the reaction zone inside the engine cylinder before the main injection. This was accomplished by injecting part of the fuel early in the cycle into the energy-cell. It is believed that one means for increasing the engine speed of rotation and the specific power output was established by this technique. Primary fuel injection timing and pressure, cooling water temperature, engine speed, main fuel injection timing, addition of cumene hydroperoxide to the fuel and energy-cell throat diameter influenced the combustion process and the engine performance. Maximum economy occurred when the primary fuel injection was at 50 B.T.C. during the exhaust stroke and of 800 lb/ins pressure. The combustion reaction rate was directly proportionate to the cooling water temperature. The delay period decreased linearly with engine speed. The engine ran smoother when the main injection was retarded and with larger throat diameter. Cumene hydroperoxide addition to the fuel had less affect on both the ignition delay and the reaction rate. The correlations which are derived from this combustion chamber, and the combustion behavior may be applied to other combustion chambers particularly the pre- and ante- combustion chambers. -87

Recommendations It is recommended that further investigations be made along the following lines: 1. Determination of optimum energy-cell throat diameter and volume, with the corresponding M.F. and P.F. injections timing. 2. The possibility of injecting the two quantities through one injection valve located in some favorable position should be examined. 3. Investigate the possibility of applying this technique in other types of combustion chambers, 4. Examine the effect of the energy cell temperature on the preflame reactions. 5. Spectroscopic analysis of the gases inside the engine cylinder at different positions could be made to detect the concentrations of the different species of intermediate and final products. 6. Examine the effect of air vitiation at high pressures and temperature on the delay period.

APPENDIX I SAMPLE CALCULATIONS Run Number 148 Readings Torque F 50 lbs. ft Time for consumption of 1/8 lb of main fuel = tm = 1.64 minute Revolution counter reading for the time tm =Nm = 2674 revs. Time for consumption of 1/16 lb of primary fuel = tp = 9.59 minute Compression pressure = P 17.5 divisions camp Maximum pressure = P 29 divisions max Location of maximum pressure 9= 15 degrees A.T.C. max Location of start of sudden pressure rise = Q. = 8 degrees A.T.C. Exhaust temperature = Th 670~F Results N 267)1 Average engine speed = 1630 r.p.m. "^m 1.64 Brakepower = FN 1 30 x 1630 9.32 B.H.P. 5250 5250 B.M.E.P. - 150.8 F 150.8 x 30 54.3 lb/in2 vs 83.48 S.F.C. 1 x 660 60o 0.491 lb/B.H.P. hr. m 8 x B.H.P. x t 8 x 9.32 x 1.64 1x 60 60 S.F.C. =...... =........~. Oo41 lb/B. H.P. hr. P 16 x B.H.P. x tp 16 x 9.52 x 9.8. B.S.F.C. S=S.F.C. = 0.491 + 0.041 0.532 lb/B.H.P. hr. Primary fuel P.F. 0.041 x......... = -- =..... x 100 = 7.87% Total fuel T.F. 0.532 Ignition delay = 19 + Qi = 19 + 8 = 27 degrees (crank angles) -89

-90T=.max i.. 15 - 8 17.5 x 7 10.65 Pmax-comp 29 - 17.5 11.5 Pcomp 17.5 Run Number 372 Location of start of sudden pressure rise = O. = 2.92 degrees B.T.C. Engine speed = N = 2000 rpm Texh = 1005 Ignition delay = (19 + Qi) x 60 x 1000 (19 - 2.92) 1000 N x 360 60 x 2000 = 1.339 milliseconds.

APPENDIX II ENGINE SPECIFICATIONS Bore (inches) = 4 1/2 Stroke (inches) = 5 1/4 Compression ratio = 14 1/2 Piston displacement = 83.48 in3 Maximum rated speed = 1800 rpm Number of revolutions per cycle = 2 Cooling system water Main injection begins 19~ before top center Intake valve opens 160 before top center Intake valve closes 38~ after bottom center Exhaust valve opens 45~ before bottom center Exhaust valve closes 20~ after top center Main injection pump AFFIA-80N-2400A } American Bosch Primary injection pump APEIB-50P-300/30 S652 B-91

APPENDIX III FUELS SPECIFICATIONS Standard Diesel Fuel H/C% by weight = 14.5 Gravity, ~A.P.I.= 43.0 Cetane Number = 51.1 Kinematic Viscosity = 1.63 Flash (Tag closed) = 130~F Sulfur % 0.113 Pour = - 30~F Heating Value = 126,000 Btu/gallon Initial Boiling Point = 335~F 10% Recovery = 3760F 50% Recovery= 437~F 90% Recovery = 486~F End Point = 5400F Temperature ~F Pressure m.m.Hg 60 0.8 80 1.6 100 2.8 120 5.0 140 8.3 160 13.3 180 21.0 200 3355.0 -92

APPENDIX IV SOLUTIONS OF THE DIFERENTIAL EQUATIONS 4-9, 4-10, 4-11 d[RCHCH] W - k2[RCHCH][02] + k3[R(CH3)CHOO][RCH2CH3] it + k1[R(CH3)CHOOH] (4-9) d[R(C5)CHOO] k2[RCHCH3][02] - k3[R(CH3)CHOO][RCCHCH] dt 2 - k3,[R(CH3)CHOO] (4-10),d[R(CH3)CHOOH] = k53R(CH3)CHOO][RCH2CH3] (4-11) dt At the oxygen pressure normally employed (few hundreds of millimeters Hg), the radical RCHCH3 reacts much faster than the radical R(CH3)CHOO and the concentration of RCHCH3 may be treated as quasi-steady. This reduces the number of equations to two..* &[RCHCH3] = Wo= W - k2[RCHCH3][02] + k3[R(CH3)CHOO][RCH2CH3] dt + kl[R(CH3)CHOOH] k2[RCHCH3][02] - k3[R(CH3)CHOO][RC2CH3] = Wo + kl[R(CH3)CHOOH] Equations (4-10) and (4-11) become: [R(CH3)CHOO] Wo + kl[R(CH3)CHOOHl - k,[R(CH3)CHOO]2 (4-10) d[R(CH))CHOOH] k [R(CH3)CHOO][RCH2CH3] (4-11) dt Using the following substitutions: k35[R(CH3)CHOO]..................., (1) [k^k1[RCICH5] k, [R(CH)CHOOH] (2) k3 [RCR2CH3] -93

-94w =, () Wo0k3' () 0 k3kl [RCH2CH ] T = lk3kl[RCCHCHt. (4) Then the system of Equations (4-10) and (4-11) can be written in the form: d = W+ T -2 (4-1o) dT d- = (4-11) d-_ But d _ d. dT WO + T - 2 dn dT dl. 2 di = 2(W' + 2 - 2) d- o Substitute 2 = y, 25 d =- dy dnT dr.. _- 2(W' + 1 - y) d dy dy + 2y = 2 Wo + 2r dr 0 Y = C e-2-q YC.F. = 1 [2W' + 2vj W +2 YP.I. = (Do + 22) = W0 +(F)[] 1 = W' + W.1 [] = W + [1 D+ q] n 0 (D/2 + ) 2 = Wo + T - 1/2.~. y general solution = Wo + r - 1/2 + C e2 at y —o - o c = 1/2 - Wc ~- y = WO + - 12 (1/2 - (l) e211 = l + (Wo- 1/2)(1 - e'21l)

-95and m2 = 1=.i = Jo -2 dT T,. -: J 0 + (W, - 1/2)(1 - e-2') 0 n7~ o By expansion (1 - e-2l) and neglecting powers 3 and up, then 1 J 2(1 - 2^Wo) + 2WI 1O and 2 t =.-.-. —-- - time of reaction in seconds. k3kl[ RCH2CH] * (1- e2) = 1 - (1 - 2TI + 21- ) = 2 - 22

APPENDIX V THERMAL THEORY OF EXPLOSION(15) According to this theory the sharp transition between slow reaction and violent explosion is explained as follows: Under certain conditions of temperature and pressure, the reaction rate reaches a critical value for which equality between the heat release due to reaction and heat loss to the surroundings became impossible. Since reaction rate coefficients are exponential functions of temperature, the overall reaction is auto-accelerated and the temperature rises. This shows the fallacy of the concept of the ignition temperature as a specific property of a subsistancej it is rather a result of the heat released by a reaction feeding back on the reaction that generates the heat and is a function of the whole system. Ignition Temperature The quantity of heat of reaction released per second ql = VQ/Na W. The rate of reaction per unit volume = W kan exp(-E/RT) molecules/second VQkan exp(-E/RT) (A-l) Na where n = 1 or 2 for unimolecular or bimolecular process respectively. ql is an exponential function with respect to T. The quantity of heat transferred through the reactor walls %q = X(T - To)s (A-2)

-97For constant X, s, q2 is a straight line function with respect to T. On Figure 42, ql and q2 are represented as a function of temperature. If the reactor wall q temperature is maintained at To, the ~~0~~~~~~~~ heat supply ql at the start is larger qi //~/ 2 than the heat removal q2. Therefore the reactants will become warmer than / / the reactor walls until it reaches / some value Ti where the temperature / will not increase more than that since q2 (heat removal) would be- come larger than ql. Thus in this To T T To Ti T 0 o 0 case the reaction does not lead to Figure 42 q-T Diagram auto-ignition. If the wall temperature is at To, ql curve does not intersect the straight line q2, In this case, the heat supply ql is larger, at all temperatures, than the heat removal q2 and thus the reactants will become continuously warmer and auto-ignition takes place. If the wall temperature is at To, the curve ql is tangent at one point to the straight line q2 and the corresponding temperature is Ti. Ti is the lowest temperature at which auto-ignition takes place and Ti is defined as the auto-ignition temperature.

-98At Ti the boundary conditions are: q = 2 (a) and -~_ ~q = a (b) dT dT VQkan exp(-E/RT) = Xs(T - T ) (a.l) E V-Qkan exp E V:Qkan exp (-E/RT) dT = Xs dT (b.l) RT2 N a substitute Xs from a.l into b.l, then E VQ kan exp(-E/RT) VQan exp(-E/RT) (b.2) RT2 Na Na('T-To) E 1 RT' T-To RT2 E = T-To (A-5) T = 1 i+ l - (4RTo/E 1 + { - (4RTo/E )} / 2 R/E 2 R/E By binomial expansion RT 2 1 + {l - 2RT/E + 2(-) + - T = 2R/E since RTo/E is a small quantity, (E; 20000 cal. To ~ 400), then terms of second order and up can be neglected and since the plus sign gives Ti above 10000~K then its solution must be rejected RT 2 (A-4).. Ti - To + (A-4) RTo2 Define AT as Ti - To = - 0 E

-99Ti = To + AT 1= 1 -- (1 - ) binomial approx. T T (l+A ) T T 1 1 2AL ^ and 1 - T (1 - m ) Ti2 T2 T i 0 0 Substitute in b.l EVkan (1- ) exp {- E/RT (1 - T = Xs (A-5) 2 0To NaRTo To T Since 2AT/To = 2RTo/E is of order 0.1, it may be neglected in the first term and Equation (A-5) becomes EQVkan exp{- E/RT + 1} = QVkan Ee exp (-E/RTo) = 1 XsNaRT2 XSNaRT o2 ao~ ~~~~~~ ~~ ~(A-6) Equation (A-6) determines To which consequently determines Ti according to the relation given by Equation (A-4). From Equations (A-4) and (A-6) one can see that the ignition temperature is a characteristic of the system as represented by the reaction rate (k,E), heat quantities and vessel geometry and material (QX,s,V and T0). Delay Period(25) * Assume that the reaction rate is constant and has its initial value and the medium is homogeneous and isotropic. The equation of energy is: net rate of evolu- heat generated by heat loss by tion of heat chemical reaction conduction CaV dT QV kan exp (-E/RT) - Xs (T-To) (A-7) a dt'Na * This assumption is not correct since the concentration of reactants decrease with time but it does not introduce substantial error.

-100Assume that the heat loss during the development of an explosion is negligible compared with the heat generated by chemical reaction(25) then Equation (A-7) becomes dT =1 kan-l Q exp (-E/RT) dt C or dT = 1 ka Qdt (A-8) e-E/RT C (28) Using the exponential approximation by replacing E/RT by a Taylor expansion E E E TT E 2 ER - (TT) - + (T-T~) T + -T) RT RTo RTo T omitting all but the first terms of the expansion since (T-To)>> To, then Equation (A-8) becomes dT- 1 ka- Qdt -E /RTo (T-To)E/RTo2 C which can be easily integrated To+ AT exp (E/RTo) exp - (T-To) E/RTo dT = 1/C kan-l 0 2 1 o RTo2 RT~2 [exp (E/RTo) * ( ) exp - (T-To) E/RTo2] E 1 Q 0 E C P- T2 exp (E/RTO)(e'1 -1) = kan- Qt E C and the induction period t, the time elapsed from the beginning of reaction to the preheat before explosion or the chemical delay, is RTo2C E/RTo ( -1) * Eka1nQ e (l-e) Todes(2' approximation gives t = — Eni - exp(E/RT) EQka

-101At the moment of the sudden increase in temperature not more than 1% of the original reactants has reacted* in a way which justifies the assumption made concerning the constancy of the reaction rate during the induction period. * Semenov [ref. 15, vol, II] p. 102.

APPENDIX VI AIR-FUEL CYCLE Compression ratio r = 14.5 Piston displacement Vs = 83.48 in3 Clearance volume Vc = 6.18 in3 Maximum pressure Pmax = 720 lb/in2 F/A = 0.0378 Volumetric efficiency = o.86b* Cooling losses (26) Compression stroke 0.75% of heat input Cobmustion 2.5% of heat input Incomplete combustion 2% of heat input Expansion stroke 6.5% of heat input Exhaust stroke 7.25% of heat input Assumptions 1. Cooling losses are distributed lineary during each individual stroke. 2. Molecular weight of combustion products = 28.925, k = 1.296 3. Residuals from the previous cycle = 0.033 4. Calculation for one pound of air As measured in an actual cycle run 3. Assumption based on previous work on the same engine. ***Products of combustion - 200% theoretical air. -102

-103P Point 1. 2' 3 T = 560~R 1 h(30) = 133.86 Btu/lb. 2 P r = 1.5742; P1 14.5 lb/in2 Vr 131.78 rl V ul = 95.47 Heat addition u = (l-f)F/A x H.V. = (1-0.033) 0.0378 x 19000 = 695 Btu. Point 2. vr - 157 9.075 Vr2 r 14. 5 ur2- 275.95 21 Cooling losses in compression stroke = 695 x 0.0075 =5.21 Btu. Actual Ur2 275.95 - 5.21 = 270.74 Btu. T2 = 1522.5~R Pr2i 59.15 V = 9.533 Pr21 Vr21 59.15 x 9.533 62.1 r Vr2 9.075 P 62.1 x 14.5 = 572 lbn2 2 1. 5742 Point 3. Cooling losses in combustion and incomplete combustion = = 695 x 0.045 31.25 Btu. h3 = (u2 + C - cooling losses + P3V2)M = (270.74 + 695 - 31.25 + 720 x 0.977 x 144 ) 28.925 778 = (1096.24 - 31.25) 28.925 = 30800 Btu/mol

-10wo4-3 = 3747 V - 11.5350 P = 3553 r3 T3 3658~R Pr Vr3 2 = 3553 x 11.335 6.185.52 in V3 f- Pr Vr2 28.925 62.1 x 9.075 Point 4. Vr41 Vr3 11 x 1 89.66 - 66.8 15.25 U i = 12980 41 Pr = 363.8 T41 = 2267~R Cooling losses = 695 x 0.065 x 28.95 = 130.9 Btu/mol. u — = 12980 - 130.9 = 12849.1 Btu/mol. Vr41 68.89 Pr42 350 T4 = 2247~R Pr42 Vr42 550 x 68.89 61 ~r4 - V 66.8 p.p _x p P =. x 720 73.2 Pr3 3555 Point P V T 1 14.5 89.66 560 2 572 6.18 1522.5 3 720 15.25 3658 4 73.2 89.66 2247

APPENDIX VII ENGINE TEST RUNS - SERIES I THROUGH VIII -105

TABLE I ENGINE TEST RESULTS - SERIES I Run N B.M.E.P. B.S.FC. deg. Teh No. R.P.M. B.H.P. Ib/in2 Ib, P.F. crank T F/A I I I _ B.H.P.bhr. T.F. anglEO"F__ 1 1625 5.09 18.1 1.057 0 54 50.7 475 0.0204 2 1610 6.14 56.2 0.701 0 34 52.7 628 0.02855 5 1600 9.15 54.5 0.567 0 29 52.5 660 0.055 4 1590 10.9 65.1 0.567 0 29 52.5 775 0.0421 5 1575 12.6 76.0 0.63355 0 29 70 860 0.0547

-107TABLE II ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 38~ A.T.C. (suc.) Run N B.M.EP. B.S.F.C. deg. Texh No. R.P.M. B.H.P. lb/in2 lb P.F. crank T OF B.H.P. hr. T.F.~ angle 6 1625 3.09 18.1 1.037 0 29 17.5 475 7 1635 3.12 18.1 0.96 16.42 27 12.5 425 8 1635 3.12 18.1 0.984 8.4 28 16.8 450 9 1635 3.12 18.1 0.971 5.13 29 22.2 460 10 1635 3.12 18.1 0.965 13.39 27 12.5 430 11 1635 3.12 18.1 0.954 13.78 26 10.5 437 12 1635 3.12 18.1 0.953 14 24 10.5 435 13 1635 3.12 18.1 0.965 15.23 24 14 435 14 1635 3.12 18.1 1.015 25.7 17 19.4 415 15 1635 3.12 18.1 1.03 29.6 19 17.5 415 16 1630 3.11 18.1 1.078 38.1 19 17.5 410 17 1625 3.09 18.1 1.16 43.6 18 14 405 18 1622 3.095 18.1 1.152 44.1 15 14 405 19 1630 3.11 18.1 1.248 50.8 19 13.2 405 20 1628 3.1 18.1 1.24 50.4 19 15.2 405 21 1628 3.1 18.1 15338 55.4 15 14 405 22 1625 3.09 18.1 1.455 60 15 18 405 23 1625 3.09 18.1 1.532 62.8 15 15.72 405 24 1625 3.09 18.1 1.58 65,5 17 12.25 405 25 1635 3.12 18.1 1.645 70.2 19 17.5 402 26 1638 3.122 18.1 1.67 72.4 19 20 402

-108TABLE III ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 38~ A.T.C. (suc.) ~~I ~ - - I I I. II k 1 I Run N | B.M.E.P. B.S.F.C. I deg. I Texh No. R.P.M. B.H.P. I b/in2 lb | P.F. crank T | ~F l||Il | ~|:B.H.P. hr. I T.F.- angle| l 27 1620 6.16 36.2 0.66 13.40 27 13 15 535 28 1625 6.19 36.2 0.654 11.85 29 18 543 29 1620 6.16 36.2 0.654 4.43 29 30 543 50 1615 6.15 56.2 0.675 5.76 29 37.5 555 31 1620 6.16 36.2 0.647 8.00 27 25 535 32 1620 6.16 56.2 0.63 2.99 27 21 555 33 1650 6.21 36.2 0.644 4.72 27 17.5 550 54 1650 6.21 56.2 0.655 14.2 24 15.15 550 35 1650 6.21 56.2 0.651 15.65 24 13.15 558 56 1655 6.22 36.2 0.67 19.15 17 10.5 528 37 1658 6.24 36.2 0.688 25.8 17 10.5 528 58 1645 6.26 36.2 0.582 30.1 17 11.05 518 39 1645 6.26 36.2 0.745 355.2 17 15.1 520 40 1642 6.25 36.2 0.791 41.5 17 13.1 510 41 1642 6.25 36.2 0.787 41.1 19 16.7 518 42 1640 6.248 36.2 0.902 49.98 19 16.7 510 45 1658 6.24 36.2. 946 52.5 19 17.65 510 44 1645 6.26 36.2 o.954 55.7 19 17.65 510 45 1648 6.27 36.2 0.988 57.15 19 17.65 510 46 1642 6.25 36.2 1.025 58.5 19 16.7 505 47 1642 6.25 36.2 1.052 60.0 19 21.4 505 48 1630 6.21 36.2 0.64 13.48 24 17.5 533 49 1632 6.22 36.2 0.614 12.65 24 17.5 540 50 1615 6.15 36.2 0.701 0 34 32.7 628

-109TABLE IV ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 38~ A.T.C. (suc.) I - I I. I. I Run | N l I| B.S.F.C. | deg. I Texh. No. R.P.M. | B.H.P. B.MM E. lb. | P.F. | crank T | ~ l l _______ | l /in | 3B.H.P. hr| T.F.0 | angle | I Il 51 1615 9.24 54.3 0.585 10.95 19 9.52 712 52 1605 9.16 54.3 0.55 7.8 23 11.1 670 53 1605 9.16 54.3 0.575 7.4 27 15 698 54 1605 9.16 54.3 0.562 6.55 27 19.25 698 55 1605 9.16 54.3 0.56 5.08 29 19.25 698 56 1598 9.12 54.3 0.564 4.63 29 19.25 708 57 1605 9.16 54.3 0.62 17.15 21 10.5 745 58 1615 9.23 54.3 0.615 15.55 19 13.15 748 59 1612 9.21 54.3 0.622 18.3 19 13.15 748 60 1615 9.25 54.5 0.621 18.9 19 15.15 748 61 1615 9.23 54.3 o.645 25.5 17 13.15 740 62 1615 9.23 54.3 0.666 28.3 17 13.15 740 63 1630 9.32 54.3 o.668 32.1 19 13.15 720 64 1620 9.25 54.3 o.686 34.6 17 16.05 704 65 1625 9.29 54.3 0.716 48.6 16 10.5 700 66 1625 9.29 54.3 0.752 41.75 16 11.11 700 67 1630 93.2 54.3 0.778 44.6 16 11.11 695 68 1622 9.27 54.3 0.805 48.9 19 13.9 670 69 1625 9.29 54.3 0.822 48.9 17 9.72 680 70 1600 9.15 54.3 0.568 51.4 27 9.06 660

-110TABLE V ENGINE TEST RESULT - SERIES II Runs at: P.F. Injection Begins at 38~ A.T.C. (suc.) Run N B.S.F.C. eg. ITexh. No. R.P.M. f B. M.E.P. |b. P |f crank | OF [____l_1| lb/in2 IB.H.P. hr T.F. | angle 71 1572 10.78 65.1 0.676 7.18 19 11.55 1000 72' 1575 10.8 65.1 0.624 7.07 21 11.55 890 73 1575 10.8 65.1 0.645 7.3 21 13 960 74 1585 10.86 65.1 0.576 5.68 27 10.1 870 75 1585 10,86 65.1 0.577 3.11 27 10.1 750 76 1595 10.93 65.1 0.645 4.o6- 24 10.1 820 77 1585 10.86 65.1 0.619 12.7 17 10.1 900 78 1585 10.86 65.1 0.599 13.3 15 9.6 875 79 1588 10.88 65.1 0.644 19.55 14 10.1 875 80 1598 10.95 65.1 0.634 22.1 15 14.65 860 81 1595 10.93 65.1 0.645 24.4 17 11.35 810 82 1610 11.03 65.1 0.622 34.3 19 10.95 760 83 1620 11.11 65.1 0.579 39.2 24 8.45 755 84 1625 11.14 65.1 0.576 44.8 27 8.45 770 85 1625 11.14 65.1 0.625 50 27 8.46 775 86 1615 11.09 65.1 0.667 51.4 27 9.06 785

-111TABLE VI ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 15~ A.T.C. (suc.) Run i N | B.S.F.C. | | deg. I Texh Run NJ B.S.F.C. dIeg. ITexh. No. R.P.M. B.H.P. B.M.E.F. | lb P.F. crank T F l|] l_ | l'Ib./in B.H.P. hr T.F. | angle | I 87 1640 3.125 18.1 0.973 15 27 12 412 88 1635 3.12 18.1 0.97 9.08 27 14 415 89 1650 3.15 18.1 0.982 12.5 29 24 415 90 1645 3.14 18.1 0.946 23.7 31 25.1 415 91 1650 3.15 18.1 0.898 19.85 27 12 395 92 1650 3.15 18.1 0.926 22.1 23 14.5 395 93 1660 3.165 18.1 0.988 35.5 21 17.45 392 94 1660 3.165 18.1 1.032 41 19 16 402 95 1655 3.16 18.1 1.07 46.2 19 12 395 96 1655 3.16 18.1 1.086 48.2 19 12 395 97 1660 3.165 18.1 1.292 50.5 19 12 395 98 1615 3.08 18.1 1.178 59.6 17 11.2 385

-112TABLE VII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 15~ A.T.C. (suc.) Run B.M.E.P. B.S.F.C. deg. eh. Thrn J iN I B.M.E.P j B.S.F.C. eg. J ITexh. No. | R.P.M. | B.H.P. I lb/in2 I lb. P.F. crank| T ~F I lI I B.H.P. hr | T.F. angle| 99 1635 6.22 36.2 0.615 19.2 19 15 503 100 1635 6.22 36.2 0.627 21.3 23 9 508 101 1640 6.248 36.2 0.611 18.05 24 10.5 512 102 1635 6.22 36.2 0.614 17.75 21 12 512 103 1635 6.22 36.2 o0.606 14.3 21 12 512 104 1635 6.22 36.2 0.60 7.83 27 12 535 105 1635 6.22 36.2 0.586 9 27 12 525 106 1628 6.2 36.2 0.63 7.32 34 60 545 107 1645 6.26 36.2 0.62 18.42 19 12 520 108 1635 6.22 36.2 0.646 24.9 21 12 510 109 1645 6.26 36.2 0.644 25.7 19 12 510 110 1645 6.26 36.2 0.678 33.4 19 12 510 111 1645 6.26 36.2 o.682 35.2 19 12 510 112 1645 6.26 36.2 0.71 40.2 17 13.5 510 113 1645 6.26 36.2 0.755 46.3 17 13.5 512 114 1645 6.26 36.2 0.825 53.9 19 9.6 517 115 1650 6.29 36.2 0.895 58.1 19 9.6 528 116 1650 6.29 36.2 0.922 62.5 19 9.6 528

-113TABLE VIII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 15~ A.T.C. (suc.) I _, I I I Run N B.M.E.P. B.S.F.C. deg. T ITexh. No. R.P.M. B.H.P. lb/in2 b | F crank OF | [ | | iBB.H.P. hr | T.F. | angle | 117 1615 9.24 54.3 0.577 10.38 31 11.25 738 118 1600 9.14 54.3 0.607 12.32 23 11.25 735 119 1610 9.2 54.3 0.555 10.12 25 7.5 705 120 1595 9.12 54.3 0.575 9.65 27 11.65 735 121 1605 9.16 54.3 0.59 10.2 27 11.65 730 122 1605 9.16 54.3 0.574 8.13 27 7.5 750 123 1615 9.24 54.3 0.548 8.45 24 10.5 705 124 1612 9.21 54.3 0.562 4.87 24 8.32 705 125 1602 9.155 54.3 0.605 17.4 29 8.5 738 126 1605 9.16 54.3 0.625 28.2 27 17 708 127 1610 9.2 54.3 o.64 33.1 21 15.1 710 128 1614 9.24 54.3 0.656 38.2 21 17 700 129 1618 9.25 54.3 0.844 40 21 17 700 130 1618 9.25 54.3 0.727 52.5 21 17 705 TABLE IX ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 15~ A.T.C. (suc.) Run N B.M.E.P. B.S.F.C. deg. Texh. No. R.P.M. B.H.P. I lb/in2 lb P.F. crank | ~F B.H.P. hr T.F. angle 131 1615 11.09 65.1 0.615 10.85 21 26 922 132 1620 11.11 65.1 o.647 10.47 19 18.2 962 133 1615 11.09 65.1 0.623 9.48 24 11.66 938 134 1610 11.03 65.1 0.546 5.17 27 18.76 765 135 1600 10.98 65.1 0.56 6.8 27 15 790 136 1612 11.05 65.1 0.586 14.95 19 15.1 855 137 1625 11.14 65.1 0.587 24.48 17 17.78 835 138 1615 11.09 65.1 0.573 15.3 19 17.78 840 139 1615 11.09 65.1 0.574 13.2 24 15.4 860 140 1630 11.19 65.1 0.5738 31.9 19 26.4 770 141 1635 11.21 65.1 0.56 33.4 21 14 740 142 l640 11.25 65.1 0.591 42.3 21 12.45 740 143 1635 11.21 65.1 0.634 51.2 24 17.5 725 144 1615 11.09 65.1 0.518 7.67 27 14 775

-114TABLE X ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 5~ B.T.C. (exh.) Run I N B.M.E.P. B.S.F.C. deg. Texh. No. R.P.M. B.H.P. lb/in | lb | P.F. J crank T O ~F _______ ______ ____ _ | B.H.P. hr | T.F. |I angle | | 145 1621 9.26 54.3 0.615 16.65 19 11.55 695 146 1628 9.3 54.3 0.581 11.42 24 9.8 710 147 1630 9.32 54.3 0.548 10.8 24 9 675 148 1630 9.32 54.3 0.532 7.88 27 10.65 670* 149 1635 9.34 54.3 0.551 6.2 29 13.32 702 150 1638 9.35 54.3 0.558 22.6 17 8 672 151 1638 9.35 54.3 0.555 23.6 17 12.3 658 152 1635 9.34 54.3 0.567 34.8 15 13.7 650 153 1648 9.42 54.3 0.58 48.15 14 13.85 631 154 1650 9.44 54.3 0.6o6 56 14 14 660 155 1652 9.45 54.3 0.643 63.6 19 16.35 662 * F/A = 0.0329 TABLE XI ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 25~ B.T.C. (exh.) Run N B.M.E.P. B.S.F.C. deg. Texh. No. |R.P.M. |B.H.P. lb/in2 lb P.F, | crank | T ~oF I. I..| B.H.P. hr T.F.0 | angle | 156 1610 9.2 54.3 0.573 9.17 24 19.5 708 157 1615 9.24 54.3 0.561 8.26 27 15 708 158 1620 9.25 54.3 0.549 8.1 27 10.5 702 159 1625 9.28 54.3 0.55 8.22 27 9.55 702 160 1655 9.54 54.3 0.54 6.65 29 13.33 692 161 1625 9.28 54.3 o.546 5.09 31 18.75 700 162 1645 9.4 54.3 0.612 19.65 19 10 675 1653 164o 9.37 54.3 0.558 17.95 19 10.72 668 164 1645 9.4 54.3 0.561 32.9 19 10 650 165 1645 9.4 54.3 0.551 35.2 23 9.22 635 166 1655 9.45 54.3 0.583 46.5 23 11.78 650 167 1654 9.45 54.3 0.592 54 23 8 655 168 1655 9.45 54.3 0.615 64.2 23 8 662

-115TABLE XII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 42~ B.T.C. (exh.) Run N | | B.M.E.P. | B.S.F.C. | | deg. IT exh No. R.P.M. B.H.P. | lb/in2 l Ib | P.F. crank T ~ ____I _ | ___1J, B.H.P.hr | T.F. I angle | 169 1632 9-33 54.3 0.558 15.05 19 12.5 668 170 1635 9.34 54.3 0.556 9.55 25 10 668 171 1635 9.54 54.5 0.55 9.42 27 10.5 650 172 1635 9.34 54.3 0.552 7.25 27 18.75 680 173 1635 9.54 54.3 0.571 17.95 16 15 695 174 i640 9.37 54.3 0.566 25.9 18 19 670 175 1645 9.4 54.3 0.555 34.9 21 12.3 625 176 1642 9.38 54.3 0.557 41.8 24 13.35 650 177 1650 9.42 54.3 0.561 52.1 27 10.72 665 178 1653 9.44 54.3 0.592 60.02 24 10.45 672 179 1653 9.44 54.3 0.6o6 65.5 24 9.8 688 TABLE XIII ENGINE TEST RESULTS - SERIES II Runs at: P. F. Injection Begins at 60~ B.T.C. (exh.) Run N B.M.E.P. B.S.F.C. deg. Texh No. R.P.M. B.H.P. | lb/in lb P.F. crank | T | I| BB.H!.P. hr T.F. angle 180 1588 9.06 54.3 0.6o 6.22 51 53.4 755 181 1605 9.16 54.3 0.602 9.62 27 14 760 182 1615 9.24 54.3 0.651 14.92 19 18 795 183 1630 9.32 54.3 0.615 23.2 19 13.65 712 184 1605 9.16 54.3 0.626 26.2 19 12 712 185 1625 9.28 54.3 0.612 36.8 21 12 712 186 1635 9.34 54.5 0.626 48.5 23 12 710 187 1647 9.41 543 o. 645 56 27 11.5 710

-116TABLE XIV ENGINE TEST RESULTS - SERIES II Runs at: P. F. Injection Begins at 50~ A.T.C. (suc.).. I l l I ~ I Ii c.i I Run N I| B.M.E.P. B.S.F.C. | deg. ITexh No. | R.P.M. I B.H.P. lb/in2 lb IP.F. crank | T F I~ ~ II I| I B.H.P. hr T.F. angle I I 188 1612 9.21 54.3 0.64 18.6 17 16.25 765 189 1605 9.16 54.3 0.639 13515 19 11 768 190 1595 9.12 54.3 0.582 6.64 27 15 745 191 1600 9.14 54.3 0.622 15.57 27 12.89 750 192 1625 9.28 54.3 0.595 20.1 17 12.5 755 193 1625 9.28 54.3 0.63 18.8 19 13.9 760 194 1635 9.34 54.3 0.615 22.2 19 12 745 195 1630 9.32 54.3 0.662 33.3 19 11.55 735 196 1625 9.28 54.3 0.734 40.6 24 11.85 705 197 1630 9.32 54.3 0.801 46.2 24 11.4 690 198 1635 9.34 54.3 0.602 9.35 27 10.5 785 199 1625 9.28 54.3 0.615 10.15 19 13.33 788 200 1625 9.28 54.3 0.589 7.4 21 11.03 745 201 1630 9.32 54.3 0.557 5.71 24 32.5 665

-117TABLE XV ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 70~ A.T.C. (suc.) Run N B.M.E.P. B.S.F.C. deg. Texh. No. R.P.M. | B.H.P. I lb/in2 l| b P.F P. crank |T ~F _I [ _i __ I| I| B.H.P. hr | T.F.' angle |I 202 1620 9.25 54.3 0.618 12.8 24 15.45 765 203 1615 9.24 54.3 0.626 9.45 27 8.34 800 204 1630 9.32 54.3 0.578 9.27 27 11.43 752 205 1635 9.34 54.3 0.58 9.13 29 8.16 745 206 1628 9.3 54.3 0.549 4.48 29 17.6 710 207 1630 9.32 54.3 0.592 18.15 23 12.15 740 208 1620 9.25 54.3 0.626 14.6 19 12.65 765 209 1630 9.32 54.3 0.654 22.8 22 9 765 210 1635 9.34 54.3 0.663 28.2 19 12.85 740 211 1635 9.34 54.3 o.694 35 16 11.35 710 212 1635 9.34 54. 3 0.76 41.7 14 11.35 695 213 1635 9.34 54.3 0.842 45.5 16 12.86 718 214 1628 9.3 54.3 0.876 46 19 10.58 730 TABLE XVI ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 95~ A.T.C. (suc.) Run N B.M.E.P. B.S.F.C. deg. Texh. No. | R.P.M. | B.H.P. | b/in2 | lb | P.F. | crank | T O F |I _|_B.H.P. hr T.F. | angle | I 215 1630 9.32 54.3 0.646 14.8 19 7.1 805 216 1620 9.25 54.3 0.619 10.3 21 9.6 790 217 1630 93.2 54.3 0.599 10.55 21 9.6 728 218 1615 9.24 54.3 0.572 7.2 - - 728 219 1625 9.28 54;3 0.541 2.48 - - 670 220 1630 9.32 54.3 0.549 11.9 21 10.4 715 221 1620 9.25 54.3 0.644 19.2 24 15.1 730 222 1630 93.2 54.3 0.647 25.5 21 7.3 768 223 1650 9.42 54.3 0.669 32.8 17 15.5 725 224 1640 9.537 54.3 0.701 36.6 16 9.6 730 225 1645 9.4 54.3 0.706 38.2 17 14.55 735 226 1650 9. 42 54.3 0.752 45.4 21 14.4 710 227 1635 9.34 54.3 0.765 49.3 27 10.3 680 228 1645 9.4 54.3 0.785 50.5 27 6.65 675

-118TABLE XVII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 120~ A.T.C. (suc.)'I I I I... I I I Run N B.M.E.P. B.S.F.C. i deg. ITexh No. R.P.M. B.H.P. lb/in2 l b P.F. | crank T ~F |I | | B.H.P. hr T.F. | angle | 229 1625 9.28 54.3 0.566 8.91 24 12.45 738 230 1615 9.24 54.3 0.569 7.53 27 12.7 738 231 1625 9.28 54.3 0.564 5.1 27 21.4 725 232 1635 9.34 54.3 0.565 11.22 22 11.25 702 233 1630 9.32 54.3 0.566 12.6 19 11.48 725 234 1615 9.24 54.3 0.654 17.95 16 9.15 795 235 1612 9.21 54.3 0.672 20.4 17 12.8 775 236 16532 9.33 54.3 0.66 24.1 14 10 735 237 1630 9.32 54.3 0.672 29.6 14 T5 720 238 1640 9.37 54.3 0.685 39.8 13 12.25 690 239 1640 9.37 54.3 0.73 44.1 19 12.85 670 240 1640 9.37 54.3 0.766 50.2 21 9 670 241 1640 9.37 54.3 0.74 54.2 24 10 670

-119TABLE XVIII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 152~ A.T.C. (suc.).... I I.. f I Run N B.M.E.P. | B.S.F.C. deg. I ITexh No. R.P.M. | BH.P. lb/in2 | lb P.F. crank T | oF,I lI I| B.H.P. hr | T.F. I angle I I 242 1615 9.24 54.3 0.66 17.9 19 13.35 773 243 1625 9.28 54.3 0.606 15.15 19 15.63 732 244 1625 9.28 54.3 0.574 14.1 21 11.65 725 245 1630 9.32 54.3 0.563 13.35 17 13.7 712 246 1630 93.2 54.3 0.556 8.3 27 6.95 695 247 1620 9.25 54.3 0.555 6.6 27 15.1 675 248 1625 9.28 54.3 o.546 6.97 27 7.15 710 249 1625 9.28 54.3 0.543 5.93 27 8.6 715 250 1620 9.25 54.3 0.553 5.65 27 10 705 251 1630 9.32 54.3 0.57 24.6 17 14.5 685 252 1628 9.3 54.3 0.601 26.1 16 8.55 695 253 1635 9.34 54.3 0.58 28.3 17 12.25 670 254 1632 9.33 54.3 0.637 28.7 14 11.1 700 255 1620 9.25 54.3 0.691 32.9 14 12.1 700 256 1625 9.28 54.3 0.736 36.2 17 8.65 695 257 1630 9.32 54.3 0.752 39.3 17 11.68 695 258 1630 9.32 54.3 0.8 42.8 17 9.46 695 259 1628 9.3 54.3 o.856 46.7 17 9.46 695

-120TABLE XIX ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at B. C. (comp.) Run N B.M.E.P. B.S.F.C. deg. Texh No. R.P.M. | B.H.P. | lb/in2 I lb P.F. | crank T o F ______[ ___ \__ _| B.H.P. hr T.F. angle | I 260 1615 9.24 54.3 0.631 15.35 22 12 758 261 1615 9.24 54.3 0.606 13.7 21 10 745 262 1625 9.28 54.3 0.57 10.83 21 10.3 725 263 1620 9.25 54.3 0.552 8.37 27 10.3 708 264 1615 9.24 54.3 0.555 7.34 27 11 730 265 1615 9.24 54.3 0.55 4.83 27 18.35 742 266 1615 9.24 54.3 0.582 11.55 17 10.7 750 267 1605 9.16 54.3 0.624 16.4 15 10.7 745 268 1615 9.24 54.3 o.644 18.8 15 12.4 750 269 1602 9.14 54.3 0.716 25.4 14 11.1 752 270 1615 9.24 54.3 0.713 28.1 15 14.1 752 271 1610 9.2 54.3 0.76 31.4 15 14.1 762 272 1615 9.24 54.3 0.792 35.3 15 14.1 762 273 1630 9.32 54.3 0.805 40 17 11 715 274 1620 9.25 54.3 0.87 42.1 19 12.57 740 TABLE XX ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 35~ A.B.C. (comp.) Run N B.M.E.P. B.S.F.C. deg. Texh. No. | R.P.M. | B..P. I b/in2 11 P.F. crank T \I[| I B.H.P. hr | T.F. angle I i 275 1625 9.28 54.3 0.615 13.5 19 13.7 750 276 1620 9.25 54.3 0.568 10.58 24 6.8 720 277 1620 9.25 54.3 0.572 10.5 24 7.85 718 278 1625 9.28 54.3 0.561 8.52 27 8.45 710 279 1612 9.21 54.3 0.55 5.26 27 15.4 705 280 1610 9.2 54.3 0. 641 15.65 19 14.16 758 281 1605 9.16 54.3 o.644 16.45 17 11 765 282 1612 9.21 54.3 0.697 22.7 17 11 760 283 1625 9.28 54.3 o0.752 3355.1 17 8.75 765 284 1615 9.24 54.3 0.825 37.5 17 8.75 765

-121TABLE XXI ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection Begins at 110~ B.T.C.(comp.) Run oN Ilb. P.FT de. e xh No. R.P.M. B.H.P. B.M.E.P. I lb P crank T lb/in2 B.H.P.hr. T.F. angle 285 1625 9.28 54.3 0.594 16.75 24 11.65 690 286 1625 9.28 54.3 0.561 11.73 24 8.3 690 287 1605 9.16 54.3 0.571 7.65 27 15 705 288 161o 9.2 54.3 0.6o6 14 17 11.65 710 289 1620 9.25 54.3 0.656 21.8 17 11.65 715 290 1615 9.24 54.3 0.68 24.5 19 15 728 291 1625 9.28 54.3 0.733 30.77 19 15 728 292 1615 9.24 54.3 0.788 34.8 19 7.8 740 293 1630 9.32 54.3 0.816 40.3 17 12.25 720 294 1630 9.32 54.3 0.841 41.9 19 16 710

-122TABLE XXII ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection begins at 75~ B.T.C. (Comp.) B.S.F.C. Run N I l lb | deFg T e No. R.P.M. B.H.P. B.M.E.P. ---.. F o. crank T F I lb/in2 B.H.P.hr. T.F. angle..._. _,_ 295 1593 9.1 54.3 0.62 14.2 27 13 745 296 1592 9.1 54.3 0.615 9.85 27 21.7 770 297 1585 9.05 54.3 0.606 9.25 29 22.75 750 298 1595 9.12 54.3 0.624 15 27 6.67 760 299 1595 9.12 54.3 0.686 19.6 24 10.83 835 300 1600 9.14 54.3 0.715 24.6 21 11.55 852 301 1585 9.05 54.3 0.766 30.3 17 15.9 880 302 1615 9.24 54.3 0.822 37.8 19 7.1 890 303 1620 9.25 54.3 0.875 42.2 21 11.42 910

-123TABLE XXIII ENGINE TESTS RESULTS - SERIES II Runs at: P.F. Injection begins at 75~ B.T.C.(Comp.) P.F. Injection pressure =1400 lb/in2 Run N BM P. Bdeg.S.F.C. 1ex Run N B.M.E P. deg. T. No. R.P.M. B.H.P. lb/in | B.H.P.hr. TF'. angle T OF.... ~.. T., angle 304 1610 9.2 54.3 0.582 8.16 27 12.25 730 305 1605 9.16 54.3 0.566 6.4 24 26 722 306 1612 9.21 54.3 0.635 16.0 21 11.55 750 307 1610 9.2 54.3 0.674 19.5 17 9.1 785 308 1610 9.2 54.3 0.704 24.2 17 10.1 785 309 1620 9.25 54.3 0.724 27.5 17 11.38 795 310 1610 9.2 54.3 0.791 33.3 19 13 850 311 1622 9.26 54.3 0.818 36.1 19 9.76 855 312 1610 9.2 54.3 0.876 38.5 17 11 870 * Irregular firing

-124TABLE XXIV ENGINE TEST RESULTS - SERIES II Runs at: P.F. Injection begins at 45~ B.T.C.(Comp.) P.F. Injection Pressure = 1400 lb/in2 B.S.F.C., Run N B.M.E P. PP. Pdeg. Texh lb/in lb. P. F. crank e No. R.P.M. B.H.Pe lb/in^ g^% T OF No RP. HB.H.P.hr. T.F. angle 313 1615 9.24 54.3 0.72 24 25 12.85 800 314 1610 9.2 54.3 0.68 15.4 25 12.85 775 315 1612 9.21 54.3 0.616 8.3 21 15.2 752 316 1632 9.33 54.3 0.565 3.6 27 12.1 705 317 1630 9.32 54.3 0.675 22.8 21 18 792 318 1625 9.28 54.3 0.656 24.9 24 7.5 775 319 1625 9.28 54.3 0.711 30.3 24 6.43 812 320 1622 9.26 54.3 0.72 36.3 27 6 825 321 1628 9.3 54.3 0.757 39.9 27 9.35 870

-125TABLE XXV ENGINE TEST RESULTS - SERIES III Runs at: P.F. Injection begins 5~ B.T.C.(exh.) P.F. Injection pressure = 1400 lb/in2 B.S.F.C. Run N B.M.E.P. lb. F deg. Tex No. R.P.M. B.H.P. lb/in2...% crank T F B.H.P.hr. T.F. angle 322 1595 9.12 54.3 0.644 10.8 19 15.45 825 323 1608 9.19 54.3 0.637 8.05 19 10.5 835 324 1600 9.14 54.3 0.586 5.6 21 9.23 780 325 1605 9.16 54.3 0.555 1.89 27 19.85 708 326 1625 9.28 54.3 0.615 18.8 17 12.6 780 327 1625 9.28 54.3 0.61 17.4 19 12.6 788 328 1625 9.28 54.3 0.63 23.7 17 14 795 329 1625 9.28 54.3 0.664 31.6 17 10.5 780 330 1635 9.34 54.3 0.679 38.7 19 14.2 795 331 1635 9.34 54.3 0.68 48.2 14 14.5 750

-126TABLE XXVI ENGINE TEST RESULTS - SERIES III Runs at: P.F. Injection begins at 5~ B.T.C.(exh.) P.F. Injection pressure = 1200 lb/in2........B.s'F'.C............... Run N B.M.E. P. lb deg. Te No.. R.P.M. B.H.P. lb./in. rank OFT l B.H.P.hr, T,F. angle 332 1605 9.16 54.3 0.594 6.75 19 12.35 750 333 1610 9.2 54.3 0.556 3.78 24 12.42 730 334 1605 9.16 54.3 0.614 10.2 19 10 792 335 1605 9.16 54.3 0.606 11.2 17 13.15 802 336 1620 9.25 54.3 0.646 19.4 14 9.28 802 337 1620 9.25 54.3 0.647 23.4 13 11.55 790 338 1630 9.32 54.3 0.605 32.9 14 11 732 339 1640 9.37 54.3 0.587 39.7 14 11 705 340 1635 9.34 54.3 0.605 46 14 12.2 720 341 1635 9.34 54.3 0.614 55.5 19 13.55 705

-127TABLE XXVII ENGINE TEST RESULTS - SERIES III Runs at: P.F. Injection begins at 50 B.T.C.(exh.) P.F. Injection Pressure = 1000 lb/in2 B.S.F.C. d1g Run N B.M.E P. PF e. T. exh No. R.P.M. B.H.P. lb/in2 ^T^-crank 0 0 B.H.P.hr. T. F. angle F 342 1603 9.15 54.3 0.585 8.15 21.6.8 775 343 1612 9.21 54.3 0.58 6.75 21 7.5 758 344 1621 9.25 54.3 0.551 5.95 23 9.85 742 345 1615 9.24 54.3 0.552 5.25 24 9.35 720 346 1612 9.21 54.3 0.555 5.15 24 8.12 735 347 1615 9.24 54.3 0.556 3.87 27 11.42 720 348 1600 9.14 54.3 0.614 11.2 19 8.75 791 349 1619 9.25 54.3 0.615 16 17 12.25 788 350 1635 9.34 54.3 0.595 26.8 15 12 755 351 1638 9.35 54.3 0.603 37.4 14 11 692 352 1638 9.35 54.3 0.599 53.2 17 11 675

-128TABLE XXVIII ENGINE TEST RESULTS - SERIES III Runs at: P.F. Injection begins at 5~ B.T.C.(exh.) P.F. Injection Pressure = 600 lb/in2 B.S.F.C.... Run N B.M.E.P. deg. T No. R.P.M. B.H.P. lb/in2 B.Hp. hr% crank T Ol~F B.H. P. hr. j T.F. angle 353 1618 9.25 54.3 0.56 6.75 23 15 758 354 1615 9.24 54.3 0.555 4.15 27 14 755 355 1608 9.19 54.3 0.56 5.05 27 11.65 750 356 1605 9.16 54.3 0.621 13.65 21 15 810 357 1602 9.14 54.3 0.58 9.25 19 13.15 800 358 1598 9.13 54.3 0.61 8.82 19 10.5 815 359 161o 9.2 54.3 0.609 12.9 17 14 812 360 1610 9.2 54.3 0.607 12.55 17 11.7 805 361 1635 9.34 54.3 0.585 18.5 15 11.45 765 362 1632 9.33 54.3 0.583 23.8 19 12 732 363 1635 9.34 54.3 0.583 29 19 12.42 722

-129TABLE XXIX ENGINE TEST RESULTS - SERIES IV Runs at: Variable cooling water temperature P.F. Injection begins at 5~ B.T.C.(exh.) Run N B.M.E.P lb. P.F. d Texh TC.W. No. RP.M. B.H.P. lb/in B. H.Phr. angle T F F 364 1615 9.24 54.3 0.56 5.5 23 10.1 763 180 365 1608 9.19 54.3 0.556 5.15 27 15 763 170 366 1625 9.28 54.3 0.552 5.26 23 14 758 158 367 1618 9.25 54.3 0.54 4.92 23 14 735 140 368 1620 9.25 54.3 0.55 4.32 29 24 720 128 369 1603 9.15 54.3 0.556 4.9 29 33 718 115

-130TABLE XXX ENGINE TEST RESULTS - SERIES V Runs at: Variable Speed Constant Racks Positions for both pumps P.F./T.F. = 15.8% F/A = 0.0396 Run N B.M.E.P. P.F. milli- deg. Texh No. R.P.M. lb/in2 T.F. seconds crank oF angle 370 1775 60.5 15.8 1.595 17 955 371 1915 59.6 15.8 1.48 17 1005 372 2000 59.6 15 8 1.339 16.08 1005 373 1700 56 15.8 1.665 17 828 374 1390 50.6 15.8 2.28 19 715 575 1150 52.45 15.8 2.75 19 610 376 950 56 15.8 3.0 17.1 585 377 1640 52.45 15.8 1.86 18 790

-131TABLE XXXI ENGINE TEST RESULTS - SERIES V Runs at: Variable Speed Constant Main Fuel Pump Rack Position F/A = 0.0329 Run N B.M.E.P. P.F. milli- deg. Th No. R.P.M. lb/in2 T.F. seconds crank OF angle 578 1625 54.3 0 3.18 31 690 379 1760 51.6 0 2.92 30.8 750 380 1860 51.6 0 2.78 31 770 381 1940 47.9 0 2.51 29.3 830 382 2040 45.2 0 2.45 29.9 950 383 1480 56 0 3.15 28 680 384 1180 54.3 0 3.81 27 590 385 850 54.3 0 3.93 20 510

-132TABLE XXXII ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 9~ B.T.C. P.F. Injection begins at 5~ B.T.C.(exh.)........................ Run N Ib. P.F. deg No. R.P.M. B.H.P. B.M.EL P. B.H.P.hr. T.F. e O 386 1625 9.28 54.3 o.6o6 22.4 0 0 752 387 1615 9.24 54.3 0.6 17.15 0 0 725 388 1611 9.21 54.3 0.589 15.9 0 0 756 389 1621 9.25 54.3 0.582 13 0 0 762 390 1621 9.25 54.3 0.592 12.65 0 0 772 391 1620 9.25 54.3 0.58 8.75 13.5 12.8 783 392 1615 9.24 54.3 0.699 3.34 23 24.3 958 393 1635 9.34 54.3 0.581 28.1 9 30.2 770 394 1635 9.34 54.3 0.607 30.4 9 26.9 765 395 1590 7.66 45.6 0.835 0 23 ~ 1040* * Max. load.

-133TABLE XXXIII ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 140 B.T.C. P.F. Injection begins at 50 B.T.C.(exh.) B3.S.F.C. Run N B.M.E.P. Ib. P.F deg T No. R.P.M. B.H.P. lb/in2 c rafx T ~F F n B.H.P.hr. T.F. angle F F/ 396 1615 3.08 18.1 1.02 0 34 oo 548 0.021 397 1645 6.26 36.2 0.798 0 29 oo 782 0.0329 398 1620 9.25 54.3 0.641 0 29 862 0.0402 399 1585 11.18 66.9 0.625 0 29 240 1045 0.0476 TABLE XXXIV ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 140 B.T.C. P.F. Injection begins at 50 B.T.C. B.S.F.C. |j, Run N B.M.E.P. lb. P.. deg. Texh No. R.P.M. B.H.P. lb/in2 B.H.P.hr. TT ange 400 1635 3.12 18.1 1.1 35.3 19 13.2 412 401 1635 3.12 18.1 0.979 35 12 19.35 420 402 1632 3.118 18.1 0.916 19.35 19 22.9 425 403 1625 3.09 18.1 0.899 13.85 27 20 418* 404 1620 3.08 18.1 0.935 10.1 29 62 458 * F/A = 0.01853

-154TABLE XXXV ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 14~ B.T.C. P.F. Injection begins at 5~ B.T.C. (exh.) I....I I 1..I I I Run N B.M.E.P. B.S.F.C. deg. ITexh No. R.P.M. B.H.P. b/in2 lb P.F. crank T I I. B.H.P. hr T.F.. I angle 405 1655 6.3 56.2 0.634 14.25 22 11.42 560 406 1660 6.32 36.2 0.619 9.99 26 11.42 585* 407 1650 6.29 56.2 0.665 6.45 24 36.3 642 408 1662 6.34 56.2 0.654 16 16 22.7 580 409 1655 6.5 56.2 0.665 21.5 14 26.9 580 410 1650 6.29 56.2 o.66 27.9 14 20.6 558 * F/A = 0.0255 TABLE XXXVI ENGINE TEST RESULTS - SERIES VI Runs att M.F. Injection begins at 140 B.T.C. P.F. Injection begins at 50 B.T.C. (exh.)..l....I. I ~.i.. Run N | B.M.E.P. B.S.F.C. | deg. ITexh No. R.P.M. |B.H.P. lb/in2 I lb |P.F. crank T ~F II | | B.H.P. hr T.F. angle 411 1605 9.16 54.3 0.584 11.7 22 18.6 750 412 1615 9.24 54.3 0.631 6.45 24 18.8 802 415 1620 9.25 54.3 0.589 8.92 22 16.5 772 414 1605 9.16 54.3 0.56 13.45 22 20.3 738* 415 1635 9.34 54.3 0.567 15.65 14 18.25 725 416 1650 9.42 54.3 0.575 21.8 12 16.2 745 417 1645 9.4 54.3 0.562 15.3 14 20 730 418 1655 9.45 54.5 0.576 24 58 14 22.5 735 419 1665 9.52 54.3 0.572 30.1 14 24.4 750 * F/A = 0.0346

-135TABLE XXXVII ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 14~ B.T.C. P.F. Injection begins at 50 B.T.C.(exh.) ^. B.S.F.C. g. Run N B.M.E.P. lb. P.F d Te No. R.P.M. B.H.P. lb/in2 B.H.P.hr. T.F. an T B..T.F. angle OF 420 1608 12.55 74.2 0.55 7.89 0 0 955 421 1595 11.7 69.6 0.815 3.87 26 18 1165 422 1600 12.19 72.4 0.549 8.13 19 31.6 942 423 1601 12.82 76 0.552 11.85 0 0 960 424 16oo 13.1 77.7 0.55 16.25 0 0 972 425 1600 13.41 79.6 0.565 18.6 0 0 1005 426 1605 13.45 79.6 0.577 19.8 14 13.35 1028* * F/A = 0.05 X' Max. Loading

-136TABLE XXXVIII ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 190 B.T.C. P.F. Injection begins at 5~ B.T.C.(exh.) Run N B.M.E.P. lb. F. deg. Te No. R.P.M. B.H.P. lb/in2 B.H.P.hr. T.F. angle D.h..r~n. Tl. F. ~ angle 427 1615 3.08 18.1 0.98 37.3 25 8.4 425 428 1605 3.059 18.1 0.974 31.9 25 13.05 412 429 1595 3.02 18.1 0.956 24.41 21 18.2 412 430 1605 3.059 18.1 0.935 17.6 29 17.6 420 431 1598 3.022 18.1 0.922 13.5 29 13.32 420 432 1591 3.015 18.1 0.882 10.55 31 - 420* 433 1605 3.059 18.1 0.93 8.2 31 * F/A = 0.0185

-137TABLE XXXIX ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 190 B.T.C. P.F. Injection begins at 50 B.T.C.(exh) B.S.F.C.... Run N B.M.E.P. lb..F deg T.h No. R.P.M. B.H.P. lb/in2 B.H.P.hr. T ane T 1B.H.P.hr, IT.F. angle T oF 434 1602 6.1 36.2 0.67 14.31 29 14.2 575 435 1632 6.22 36.2 0.618 9.25 29 13.32 570* 436 161o 6.13 36.2 0.638 7.74 31 75 588 437 16oo 6.09 36.2 0.664 13.9 24 17.6 575 438 1618 6.15 36.2 0.648 19.6 23 12.8 560 439 1620 6.16 36.2 0.657 27.8 21 11.72 545 *F/A = 0.0255

-138TABLE XL ENGINE TEST RESULTS - SERIES VI Runs at: M.F. Injection begins at 19~ B.T.C. P.F. Injection begins at 5~ B.T.C.(exh.) B.S.F.C. I I Run N B.M.E.P. P.F. deg. T No. R.P.M. B.H.P. lb/in2 B.X.P.hr. 0 cnk T exh N.PB.H.P.hr. T.F. angle 440 1605 12.83 76 0.626 15 19 16.8 1020 441 1590 13.2 78.6 0.706 17.85 19 17.5 1155 442 1610 13.95 82.2 0.66 7.55 21 32 1165* 443 1615 13.09 76.9 o.65 5.15 29 32 1180 444 1580 12.05 72.4 0.777 3.5 26 21.66 1230 * F/A = 0.0585

TABLE XLI ENGINE TEST RESULTS - SERIES VII Runs at: Fuel is a mixture of 1% by volume of cumene hydroperoxide in Diesel fuel R B.S.F.C. Run N B.M.E.P. lb. P.F deg. T No. R.P.M. B.H.P. lb/in2 T xhPF M.F. B.H.P.hr. T.F. angle 445 1625 9.28 54.3 0.571 0 34 760 - no 446 1645 9.4 54.3 0.587 13.1 29 19.7 800 no no o 447 1615 9.24 54.3 o.608 12.7 24 12 770 yes no 448 1620 9.25 54.3 0.607 13.2 19 17.7 765 yes yes 449 1605 9.16 54.3 0.577 0 24 48 760 - yes 450 1615 9.24 54.3 0.642 12.1 24 43.4 860 no yes no = no additive was added to the fuel. yes = additive was added to the fuel.

-140TABLE XLII ENGINE TEST RESULTS - SERIES VIII Runs at: Throat diameter = 0.196 inch........a............ B.S.F.C. Run N B.M.E.P. lb. P.F deg. T No. R.P.M. B.H.P. b/in2 B.H.P.hr. T.F. angle 451 1632 9.33 54.3 0.601 13.45 19 15.55 680 452 1625 9.28 54.3 0.6218 10.1 29 35.2 742 453 1615 9.24 54.3 0.6216 6.25 29 58 725 454 1628 9.3 54.3 0.599 11.3 19 21 685 455 1618 9.248 54.3 0.6o4 16.6 16 18.92 610 456 1625 9.28 54.3 0.58 18.65 14 17 600 457 1623 9.278 54.3 0.582 25.6 16 18 590 458 1616.5 9.238 54.3 0.568 28.9 16 18 6oo 459 1640 9.37 54.3 0.594 37 19 15.65 620 460 1650 9.42 54.3 0.607 44 19 10.85 622 461 1638 9.35 54.3 o.645 50.4 19 14.2 622 462 1620 9.25 54.3 0.585 0 31 64 635 463 1575 9.0 54.3 0.59 7.28 930 464 1575 9.0 54.3 0.654 0 1050

TABLE XLIII ENGINE LOG SHEET Eng. Mfg. Nordberg Serial No. 1-AH-900 Dynamometer D-C cradle, Type TLC, GE, Model UFS1-AH, (diesel), 4-stroke No. Cyl. 1 Link Unibeam Bore 4-1/2, Stroke 5-1/4 in., Pist. Disp. 83.48 cu. in. Prim. Fuel Diesel Main Fuel Diesel Comp. Ratio 14.5 P. Inj. begins 5~ B.T.C.(Exh.) Main Inj. begins 19~ B.T.C. Barometer 28.93 in. hg. Room Temp. 72 ~F Date: September 30, 1959 Cooling Water Temp. 140 ~F Oil Sump Temp. 16o ~F Prim. Fuel 1/16 lb. Max. Press Run Torque Total Time Avg. Obs. B.M.E.P. Main-Fuel Time lb/b.h.p.- P.F. B.S.F.C. Comp. Qmx mx Ign. Ing. Ex. No. lb. ft. Revs. R.P.M. B.H.P. lb/in2 lb/b.h.p.- hr. T.F. lb/b.h.p.- Press. deg. St. Delay Temp. Nm tm N hr. tp hr. Div. A.T.C. Div. Qi 1i deg. I 145 30 2562 1.58 1621 9.26 54.3 0.511 3.93 0.103 16.65 0.615 14.5 10 28 T.C. 19 11.55 695 H 146 30 2551 1.565 1628 9.3 54.3 0.515 6.10 0.o66 11.42 0.581 14 12 26 5'~A 24 9.8 710 1 147 30 2682 1.645 1630 9.32 54.3 0.49 6.94 0.058 10.8 0.548 18 12 31 5~A 24 9 675 148 30 2674 1.64 1630 9.32 54.3 0.491 9.8.o4l 7.88 0.532 17.5 15 29 8 A 27 10.65 670 149 30 2541 1.555 1635 9.34 54.3 0.517 11.8 0.034 6.2 0.551 15 18 24 10~A 29 13.32 702 150 30 3043 1.86 1638 9.35 54.3 0.432 3.19 0.126 22.6 0.558 16 5 30 2~B** 17 8 672 151 30 3106 1.895 1638 9.35 54.3 0.424 3.07 0.131 23.6 0.555 16 8 29 2~B 17 12.3 658 152 30 3554 2.165 1635 9.34 54.3 0.372 2.o6 0.195 34.8 0.567 16 8 30 4~B 15 13.7 650 153 30 4351 2.64 1648 9.42 54.3 0.301 1.425 0.279 48.15 0.58 16 8 31 5~B 14 13.85 631 154 30 4937 2.99 1650 9.44 54.3 0.267 1.175 0.339 56 o.6o6 17.5 5 30 5~B 14 14 660 155 30 5633 3.405 1652 9.45 54.3 0.234 0.975 0.409 63.6 0.643 18 10 29 T.C. 19 16.35 662 A A.T.C. ** B = B.T.C.

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14315. Semenov, N. N. Some Problems in Chemical Kinetics and Reactivity. Vol. I, II, Princeton University Press, 1959. 16. Bone, W. A. and Gardner, J. B. "Comparative Studies of the Slow Combustion of Methane, Methyl Alcohol, Formaldehyde and Formic Acid," Proc. Roy. Soc. (London), A, 154, (1936) 297. 17. Todes, 0. M. "Acta Physiocochimica' U.R.S.S. 5, 785 (1936). 18. Gydon, A. G. Spectroscopy and Combustion Theory, London: Chapman and Hall Ltd, (1942) 49. 19. Townend, D. T. A. "Ignition Regions of Hydrocarbons," Chem. Rev. 21, (1937) 259: Townend, D. T. A. and Maccormac, M. "The Spontaneous Ignition Under Pressure of Typical Knocking and Non-Knocking Fuels," J. Chem. Soc., London (1938) 238. 20. Walsh, A. D. "Processes in the Oxidation of Hydrocarbon Fuels," Trans. Faraday Soc., 34 (1947), 297, 305. 21. Bateman, L., Hughes, H. and Morris, A. L. "Bydroperoxide Decomposition in Relation to the Initiation of Radical Chain Reactions," Disc., Faraday Soc., No. 14, (1953) 190. 22. Dixon, H. B. "Ignition Temperature of Gases," Ibid (1934) 1382. 23. Mullins, B. P. "Combustion in Vitiated Air," Selected Combustion Problems, Agard, London: Butterworth Sc. Publ. (1954). 24. Miller, R. E. "Some Factors Governing the Ignition Delays of a Gaseous Fuel," Seventh Symposium on Combustion, London: Butterworth Sc. Publ. (1958). 25. Gray, P. and Harper, M. J. "The Thermal Theory of Induction Periods and Ignition Delays, Seventh Symposium on Combustion, London: Butterworth Sc. Publ. (1959) 425. - 26. Vicent, E. T. Supercharging the Internal Combustion Engine, New York: McGraw-Hill Company, 1948. 27. RVgener, H. "Z. Elektrochem," 53 (1949), 389. 28. Kamentskii, F. D. A. Zhur. Fiz. Khim. 13 (1939) 738, Kamentskii, F. Acta Pbysicochim. U.R.S.S. 20 (1945) 729. 29. Todes, D. M. Acta Physicochim U.R.,SS. (1936) 789. 30. Keenan, J. H., and Kaye, J. Gas Tables New York: Wiley and Sons, Inc. (1956).

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