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+//Effect of molecular contraction
+clc,clear
+//Given:
+r=7 //Compression ratio
+CV=44000 //Calorific value of the fuel in kJ/kg
+A_F=13.67 //Air fuel ratio of the mixture
+cv=0.718 //Specific heat at constant volume in kJ/kgK
+n=1.3 //Polytropic index
+P1=1,T1=67+273 //Pressure and temperature at the beginning in bar and K
+//Solution:
+//Refer fig 3.22
+C=12 //Atomic mass of Carbon(C)
+H=1 //Atomic mass of Hydrogen(H)
+O=16 //Atomic mass of Oxygen(O)
+p=23 //Percentage of oxygen in air by mass
+//Stoichiometric equation of combustion of fuel (C6H14)
+//   [C6H14] + x[O2]   =   y[CO2] + z[H2O]
+//Equating coefficients
+x=9.5,y=6,z=7 //Coefficients of stoichiometric equation
+A_F_g=x*2*O/(6*C+14*H)*100/p //Gravimetric air fuel ratio
+MS=A_F_g/A_F*100 //Actual mixture strength in percent
+//Combustion is incomplete
+//Stoichiometric equation of incomplete combustion of fuel (C6H14)
+//    MS/100[C6H14] + x[O2] = a[CO2] + b[CO] + c[H2O]
+//Equating coefficients
+a=4.39,b=2.36,c=7.87 //Coefficients of stoichiometric equation
+//Stoichiometric equation of combustion of fuel (C6H14) by adding Nitrogen
+//   MS/100[C6H14] + x[O2] + x*79/21[N2] = a[CO2] + b[CO] + c[H2O] + x*79/21[N2]
+m1=MS/100+x+x*79/21 //Moles before combustion
+m2=a+b+c+x*79/21 //Moles after combustion
+Me=(m2-m1)/m1*100 //Molecular expansion in percent
+T2=T1*r^(n-1) //Temperature at 2 in K
+m_c=A_F+1 //Mass of charge in kg
+T3=CV/(m_c*cv)+T2 //Temperature at 3 in K
+T3=round(T3)
+P3=P1*r*(T3/T1) //Pressure at 3 in bar (printing error)
+//Temperature and pressure considering molecular expansion
+T3!=T3 //Temperature remains same at 3 in K
+P3!=P3*m2/m1 //Pressure at 3 in bar
+//Results:
+printf("\n\t The molecular expansion = %.2f percent\n",Me)
+printf("\n (a)Without considering the molecular contraction\n\t The maximum pressure, P3 = %.2f bar\n\t The maximum temperature, T3 = %.0f K",P3,T3)
+printf("\n (b)Considering the molecular contraction\n\t The maximum pressure, P3 = %.2f bar\n\t The maximum temperature, T3 = %.0f K",P3!,T3!)
+//Answer in the book is wrong