Hi,
In the code you have provided, the same variable kk is being used to loop over both the variable arrays p_ratio_array and p_ratio_int_array. Further, to iterate through all combinations of the 2 input variables, t_cost and n_th_count need to be 2D matrices.
Here is a modified version of your code which will give the surface plot. Comments have been added only where changes are made. You may need to make some changes to get the other 3 line plots as per your requirement.
p1= 97000;
t1=285.15;
t5=1493.15;
y=1.4;
cp=1005;
n=0.9;
W_out= (3.6*(10^7))/0.96;
a=50;
optimal_cost=1000000000000000000;
best_p_ratio=0;
best_p_int_ratio=0;
optimal_efficiency=0;
p_ratio_array= linspace(1.5,10,a);
p_ratio_int_array= linspace(0.1,0.9,a)';
t_cost= zeros(a,a); %2D Array creation for Total Cost
n_th_count= zeros(a,a); %2D array creation for efficiency counting
for kk1=1:a % Using variable kk1 instead of kk
p_ratio=p_ratio_array(kk1); % Using variable kk1 instead of kk
for kk2=1:a % Using variable kk2 instead of kk
p_ratio_int=p_ratio_int_array(kk2); % Using variable kk2 instead of kk
t2=t1*((p_ratio*p_ratio_int)^((y-1)/(n*y)));
w1_2=cp*(t1-t2);
t3=t1;
q2_3=cp*(t3-t2);
t4=t3*((p_ratio/(p_ratio*p_ratio_int))^((y-1)/(n*y)));
w3_4=cp*(t3-t4);
q4_5=cp*(t5-t4);
t6=t5*((1/p_ratio)^((n*(y-1))/y));
w5_6=cp*(t5-t6);
n_th_count(kk1,kk2)=((w5_6+(w1_2+w3_4))./q4_5).*100; % Using 2D indexing (kk1,kk2) instead of kk
n_th=n_th_count(kk1,kk2); % Using 2D indexing (kk1,kk2) instead of kk
m_dot= W_out./ (w5_6+(w1_2+w3_4));
t_cost(kk1,kk2)= ( 15000.*((m_dot).^0.85).*((p_ratio).^2.5) )+( (25000.*m_dot).*25 ); % Using 2D indexing (kk1,kk2) instead of kk
total_cost=t_cost(kk1,kk2); % Using 2D indexing (kk1,kk2) instead of kk
if total_cost<0
break
end
iftotal_cost<optimal_cost
best_p_ratio=p_ratio;
best_p_int_ratio=p_ratio_int;
optimal_cost=total_cost;
optimal_efficiency=n_th;
end
end
end
hold on
figure(1)
AX=plot(p_ratio_array,n_th_count,'bo-', ...
'LineWidth', 1, 'MarkerSize', 5, ...;
'MarkerFaceColor', 'r', 'MarkerEdgeColor', [.5, .9, .7]);
xlabel('Pressure Ratio');
ylabel('Efficiency (%)');
title('Pressure Ratio Vs Efficiency')
figure(2)
plot(p_ratio_int_array,n_th_count,'bo-', ...
'LineWidth', 1, 'MarkerSize', 5, ...;
'MarkerFaceColor', 'r', 'MarkerEdgeColor', [.5, .9, .7]);
xlabel('Pressure Ratio Intercooler');
ylabel('Efficiency (%)');
title('Pressure Ratio Intercooler Vs Efficiency')
figure(3)
plot(n_th_count,t_cost,'bo-', ...
'LineWidth', 1, 'MarkerSize', 5, ...;
'MarkerFaceColor', 'r', 'MarkerEdgeColor', [.5, .9, .7]);
xlabel('Efficiency (%)');
ylabel('Total Cost');
title('Efficiency Vs Total Cost');
figure(4)
[X,Y]=meshgrid(p_ratio_array,p_ratio_int_array); % Using meshgrid to get X,Y coordinates for surface plots
surf(X,Y,abs(t_cost)) % Surface plot of magnitude of t_cost (magnitude taken because t_cost is of type complex double)
xlabel('Pressure Ratio');
ylabel('Total Cost');
zlabel('Intercooler Pressure Ratio');
