clear; clc; disp('Example 8.23'); // aim : To determine // (a) the actual quantity of air supplied/kg of fuel // (b) the volumetric efficiency of the engine // given values d = 300*10^-3;// bore,[m] L = 460*10^-3;// stroke,[m] N = 200;// engine speed, [rev/min] C = 87;// %age mass composition of Carbon in the fuel H2 = 13;// %age mass composition of H2 in the fuel mc = 6.75;// fuel consumption, [kg/h] CO2 = 7;// %age composition of CO2 by volume O2 = 10.5;// %age composition of O2 by volume N2 = 7;// %age composition of N2 by volume mC = 12;// moleculer mass of CO2,[kg/kmol] mH2 = 2;// moleculer mass of H2, [kg/kmol] mO2 = 32;// moleculer mass of O2, [kg/kmol] mN2 = 28;// moleculer mass of N2, [kg/kmol] T = 273+17;// atmospheric temperature, [K] P = 100;// atmospheric pressure, [kn/m^2] R =.287;// gas constant, [kJ/kg k] // solution // (a) // combustion equation by no. of moles // 87/12 C + 13/2 H2 + a O2+79/21*a N2 = b CO2 + d H2O + eO2 + f N2 // equating coefficient b = 87/12;// [mol] a = 22.7;// [mol] e = 10.875;// [mol] f = 11.8*b;// [mol] // so fuel side combustion equation is // 87/12 C + 13/2 H2 +22.7 O2 +85.5 N2 mair = ( 22.7*mO2 +85.5*mN2)/100;// mass of air/kg fuel, [kg] mprintf('\n (a) The mass of actual air supplied per kg of fuel is = %f kg\n',mair); // (b) m = mair*mc/60;// mass of air/min, [kg] V = m*R*T/P;// volumetric flow of air/min, [m^3] SV = %pi/4*d^2*L*N/2;// swept volume/min, [m^3] VE = V/SV;// volumetric efficiency mprintf('\n (b) The volumetric efficiency of the engine is = %fpercent\n',VE*100); // End