%state variables
p1=101325
t1=500
gamma=1.4;
t3=2300;
% engine geometric parameters
bore = 0.1;
stroke = 0.1;
con_rod = 0.15;
cr= 12;
% calculating the swept volume and swept clearance
v_swept = (pi/4)*bore^2*stroke;
v_clearance = v_swept /(cr-1);
v1= v_swept+v_clearance
v2= v_clearance
% state variables at state point 2
p2=p1*cr^gamma;
t2= p2*v2*t1/(p1*v1);
constant_c=p1*v1^gamma;
v_compression=enginekinematics(bore,stroke,con_rod,cr,0,180);
p_compression=constant_c./v_compression.^gamma;
%state variables at state point 3
v3=v2;
p3= p2*t3/t2;
constant_c=p3*v3^gamma;
v_expansion=enginekinematics(bore,stroke,con_rod,cr,180,360);
p_expansion=constant_c./v_expansion.^gamma;
%state variables at state point 4
v4=v1;
p4=p3*(v3/v4)^gamma
%thermal efficiency of otto cycle
Thermal_efficiency = 1/((cr)^(gamma-1));
figure(1)
hold on
plot(v_compression,p_compression)
plot(v_expansion,p_expansion)
plot([v2 v3],[p2 p3],'color','g')
plot([v4 v1 ], [p4 p1],'color','r')
xlabel('Volume')
ylabel('Pressure')