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+clc;funcprot(0);//EXAMPLE 20.4
+// Initialisation of Variables
+p1=1;........//Suction pressure in bar
+t1=293;.......//Suction temperature in K
+p2=6;..........//Discharge pressure in bar
+t2=453;.......//Discharge temperature in K
+N=1200;.........//Compressor rpm
+Ps=6.25;........//Shaft power in kW
+ma=1.7;........//Mass of air delivered in kg/min
+D=0.14;......//Engine bore in m
+L=0.10;.......//Engine stroke in m
+R=287;..........//Gas constant in kJ/kgK
+//Calculations
+Vd=(%pi/4)*D*D*L*N;.........//Displlacement volume in m^3/min
+FAD=ma*R*t1/(p1*10^5);........//Free air delivered
+etav=FAD/Vd;.....//Volumetric efficiency 
+disp(etav*100,"Volumetric Efficiency in %:")
+n=1/(1-((log(t2/t1))/(log(p2/p1))));........//Index of compression
+IP=(n/(n-1))*(ma/60)*(R/1000)*t1*(((p2/p1)^((n-1)/n))-1);..........//Indicated power in kW
+disp(IP,"Indicated power in kW:")
+Piso=((ma/60)*(R/1000)*t1*(log(p2/p1)));..........//Isothermal power
+etaiso=Piso/IP;..............//Isothermal efficiency
+disp(etaiso*100,"Isothermal efficiency in %:")
+etamech=IP/Ps;...........//Mechanical efficiency
+disp(etamech*100,"Mechanical efficiency in %:")
+etao=Piso/Ps;........//Overall efficiency
+disp(etao*100,"Overall efficiency in %:")
+