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3v Specific Volume ( m )LIST OF ABBREVIATIONS, SYMBOLS AND SUBSCRIPTS (CONTINUED)viMole of Particular Combustion ProductyiMole Fraction of Particular Combustion Productε Half Stroke to Rod Ratio (s/2 l)θCrank AngleθStart of burningθsbθ s , Wθ WωηηTτεφαβδBurn Duration AngleStart of Water InjectionWater Injection Duration AngleEngine Speed (rad/s)Indicated Thermal efficiencyThermal EfficiencyCharacteristic TimeMolar Fuel to Air RatioFuel to Air Equivalence RatioCarbon Atom Concentration (in the fuel)Hydrogen Atom Concentration (in the fuel)Nitrogen Atom Concentration (in the fuel)SubscriptsabfimuwAirBurned gasFuelParticular Combustion ProductMixtureUnburned GasWaterxii
CHAPTER 1INTRODUCTION1.1 BackgroundGenerally the injection of water into the combustion chambers of the internalcombustion engine is a method for cooling engine by adding water to the incomingfuel-air usually mixed together in the intake system prior to the engine cylinder,allowing for greater compression ratios and largely eliminating the problem of engineknocking (detonation). This system normally used in conjunction with a superchargeror turbocharger, altered spark ignition timing, and other modifications.In a piston engine, the initial injection of water cools the fuel-air mixturesomewhat, which increases its density and hence the amount of mixture that enters thecylinder. But the greater effect comes later during combustion when the water takes insignificant amounts of heat energy as it converts from liquid to gas (steam). Thisincreases piston pressure (torque), reduces peak temperature (adiabatic temperature)and resultant NOx formation, and reduces the amount of heat energy absorbed into thecylinder walls. The duration of combustion stroke is said to be longer, preventingdetonation and temperature in engine chamber more than other stroke.1.2 Literature ReviewThe use of water as supplement to fuel-air mixture has been consideredrepeatedly since the early development of internal combustion engine (ICE).Observations generally regard water effects on the system to decrease the maximumexhaust temperature, detonation, knock and means to control emission of the engine ifwater injected is optimum volume. Water injections into the spark ignition enginehave investigated for study since 1930, this method was used in air force. After that in1953, it was tested for a motor vehicle by Ricardo [1], the results had shown thatwater injection really represented a new way to avoid detonation and the engine couldreduce NOx emissions. Nicholls [2] worked on finding the method to control NOx byusing water-fuel emulsion emission. It was found that 10% water in gasolinecaused10-20%reductions in nitro geno xides. For analysis performance was describedby Tsao [3], he described that the power output was increased in the order of 3.8 to14% when the based fuel containing 5 to 15% water was used by these preliminaryperformance data conducted with a single cylinder engine. From German research,Tschalamoff and Laab [4], had reported the effects of water presence in fuel on SIengines. They indicated that the NOx content in the exhaust gas dropped by 1.3 % for1 % additional of water to emulsified fuel. Water injection effects in a single cylinderCFR engine was described by Lanzafame [5]. His results had shown thatNitrogenoxide (NOx) reductions of over 50% with water injection/fuel ratio in therange of 1 to 1.25.All observations were attributed water injection is interested in emissionsbecause it could potentially decrease Nitrogenoxide (NOx) in exhaust, by addingwater to the incoming fuel-air mixed together in the intake system before combustionprocess. If water was injected directly into the piston cylinder after combustion
Page 1 and 2: ANALYSIS OF WATER INJECTION INTO HI
Page 3 and 4: Thesis CertificateThe Graduate Coll
Page 5 and 6: ชื่อ : นายปรม
Page 7 and 8: TABLE OF CONTENTSPageAbstract (in E
Page 9 and 10: LIST OF TABLESTablePage3-1 Solution
Page 11 and 12: LIST OF FIGURES (CONTINUED)FigurePa
Page 13: LIST OF ABBREVIATIONS, SYMBOLS AND
Page 17 and 18: 31.6.6 Water injected is assumed to
Page 19 and 20: 6for these working fluid models can
Page 22 and 23: CHAPTER 3METHODOLOGY FOR ANALYSIS O
Page 24 and 25: 11perform the necessary calculation
Page 26 and 27: 13h b P T w−0.2 0.8 −0.55 0.8=
Page 28 and 29: 15the procedure required Nitrogen(
Page 30 and 31: 171N22 NEq.3-461 1O+2N2 NOEq.3-472
Page 32 and 33: 19∂y1 cy ∂y1 cy ∂y 1 c ∂y 1
Page 34 and 35: 211/2( cy )∂y ∂∂c ∂y∂T
Page 36 and 37: 23[ A][ ∂y/ ∂ P] + [ ∂f / ∂
Page 38 and 39: 25⎛ • • •ln ln ⎞⎛⎞( )
Page 40 and 41: 27( θ= −π)θ>θ bθ>θ W( θ=π
Page 42 and 43: CHAPTER 4RESULTS AND DISCUSSIONThis
Page 44 and 45: 31FIGURE 4-1 Comparison of an actua
Page 46 and 47: 33FIGURE 4-4 Schematic of the port
Page 48 and 49: 35Temperature (K)250023002100190017
Page 50 and 51: 37cylinder temperature. So, a more
Page 52 and 53: 39Thermal efficiency (%)43424140393
Page 54 and 55: 41Theoretically, the high useful co
Page 58 and 59: 45injection-fuel ratio increases gr
Page 62 and 63: 49When considering relative tempera
Page 64 and 65:
51Temperature (K)240021001800150012
Page 66 and 67:
53When considering relative tempera
Page 68 and 69:
55Temperature (K)220019001600130010
Page 70 and 71:
CHAPTER 5CONCLUSIONS AND SUGGESTION
Page 72 and 73:
REFERENCES1. Ricardo, H.R. The High
Page 74:
APPENDIX ADerivative equations of i
Page 78 and 79:
64TABLE A-3 Curve fit coefficients
Page 80 and 81:
66TABLE A-5 Curve fit coefficients
Page 82 and 83:
68The following is the derivative v
Page 84 and 85:
70From the definition of entropyh =
Page 86 and 87:
72• ⎛ ⎞ • ⎛Tb∂u •b∂
Page 88 and 89:
74• ⎛1 ⎞ •∂u ⎛∂ ∂
Page 90 and 91:
76⎛ • • •ln ln ⎞⎛⎞( )
Page 92 and 93:
78The following is the derivative v
Page 94 and 95:
80From the definition of entropy h
Page 96 and 97:
82• ⎛ Tb u ⎞ • • ⎛bmTb
Page 98 and 99:
84• ⎛1 ⎞ • •∂u ⎛ ⎞
Page 100 and 101:
86• • • ⎛ u ⎞bmb( hW ub)
Page 102 and 103:
88Appendix D MATLAB program scripts
Page 104 and 105:
90[thetawater,pTbWQlHl2]=ode45('Rat
Page 106 and 107:
92-0.69353550E-14 -0.14245228E+05 0
Page 108 and 109:
940.21*(1-phi) 0 0]';dcdT=0;else %
Page 110 and 111:
96dfdp=zeros(4,1);dYdT=zeros(11,1);
Page 112 and 113:
98dcdT(1)=-dKdT(1)*sqrt(patm)/K(1)^
Page 114 and 115:
100Iter=Iter+1;[hb,u,v,s,Y,cp,dlvlT
Page 116 and 117:
102yprime(2)=-Const1/cpb/x*Qconvb+v
Page 118 and 119:
104masswaterin=massfuel*mwpmf;% Tot
Page 120 and 121:
106savefile = 'Volume.mat';RTWV=RTW
Page 122 and 123:
108p=pTarray(:,1);T=pTarray(:,2);hc
Page 124 and 125:
110gamma_der_tautau = 0;for i = 1 :
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