Project 2 - Rankine cycle Simulator

The working fluid is pumped from low to high pressure. As the fluid is a liquid at this stage, the pump requires little input energy.

The high-pressure liquid enters a boiler, where it is heated at constant pressure by an external heat source to become a dry saturated vapour. The high-pressure liquid enters a boiler, where it is heated at constant pressure by an external heat source to become a dry saturated vapour. The input energy required can be easily calculated graphically, using an enthalpy-entropy chart(h-s chart, or mollier diagram), or numerically, using steam table or software.

clear all 
close all
clc
disp('RANKINE CYCLE');
disp('process 1-2  isentropic expoansion in turbine')
disp('process 2-3 constant pressure heat rejection in condenser')
disp('process 3-4 isentropic compression in pump')
disp('process 4-1 consant pressure heat addition in boiler')
% accepting input from user
T1=input('enter the turbine inlet temp,t1 (in deg.c)=');
p1=input('enter the turbine inlet pressure,p1 (in bar)=');
p2=input('enter the turbine outlet pressure,p2 (in bar)=');
% getting data from xsteam file and defining values

%state 1
h1=XSteam('h_pT',p1,T1); 
s1=XSteam('s_pT',p1,T1); 

%state 2
s2=s1 ;                
sf2=XSteam('sL_p',p2); 
sg2=XSteam('sV_p',p2);
x2=(s2-sf2)/(sg2-sf2);
hf2=XSteam('hL_p',p2);
hg2=XSteam('hV_p',p2);
h2=hf2+(x2*(hg2-hf2));

%state 3
p3=p2;                   
s3=XSteam('sL_p',p3);
h3=XSteam('hL_p',p3);

%state 4
s4=s3;
p4=p1;

%work done by turbine
wt= h1-h2;
%work done by pump
v3=XSteam('vL_p',p3);
wp=v3*(p4-p3)*100;

%pump work=h4-h3, therefore 
h4=h3+wp;

%net work done
wnet=wt-wp;

% calculating thermal efficency
qin=h1-h4; % heat in
qout=h2-h3; %heat out
therm_eff= (wnet/qin)*100;

%specific steam consumption  Specific Steam Consumption or Steam Rate (SSC)
% is the mass flow rate of steam required to produce 1 kW net work output
ssc=(3600/wnet);

%determining temperature at remaining state points
T3=XSteam('Tsat_p', p3);
T2=T3;
cp4=XSteam('Cp_ps',p4,s4);
cv4=XSteam('Cv_ps',p4,s4);
k=cp4/cv4;
T4=T3/((p3/p4)^((k-1)/k));

%At vapour and liquid line
T6=XSteam('Tsat_P',p1);
s5=XSteam('sL_p',p1);
s6=XSteam('sV_p',p1);
h5=XSteam('hL_p',p1);
h6=XSteam('hV_p',p1);
T5=T6;

% plotting the saturation curve
T=linspace(1,375,1000);
for i= 1:length(T)
    sf(i)=XSteam('sL_T', T(i));
    sg(i)=XSteam('sV_T', T(i));
    hf(i)=XSteam('hL_T', T(i));
    hg(i)=XSteam('hV_T', T(i));
end

%plotting T-S diagram
figure(1)
hold on
plot(sf,T,'color','g')
plot(sg,T,'color','g')

plot([s1 s2],[T1,T2],'k','linewidth',2)
plot([s2 s3],[T2 T3,],'k','linewidth',2)
plot([s3 s4],[T3 T4,],'k','linewidth',2)
plot([s4 s5],[T4 T5,],'k','linewidth',2)
plot([s5 s6],[T5 T6,],'k','linewidth',2)
sc1=linspace(s6,s1,1000);
for i=1:length(sc1)
    Tc1(i)= XSteam('T_ps',p1,sc1(i));
end
plot(sc1,Tc1,'k','LineWidth',2)
text(s1+0.1,T1,'1')
text(s2+0.1,T2,'2')
text(s3,p1,T3-20,'3')
text(s4,T4+20,'4')
title('TEMPERATURE VS ENTROPY PLOT')
xlabel('ENTROPY (S) KJ/KGK')
ylabel('TEMPERATURE (T) DEG.C')
legend('SATURATION CURVE')

%plotting H-S diagram
figure(2)
hold on
plot(sf,hf,'color','b')
plot(sg,hg,'color','b')
plot([s1 s2],[h1 h2],'k','LineWidth',2)
plot([s2 s3],[h2 h3],'k','linewidth',2)
plot([s3 s4],[h3 h4],'k','linewidth',2)
hc= linspace(h4,h5,100);
for j=1:length(hc)
    sch(j)=XSteam('s_ph',p1,hc(j));
end
plot(sch,hc,'k','LineWidth',2)
plot([s5 s6],[h5 h6],'k','LineWidth',2)
for k=1:length(sc1)
hc1(k)=XSteam('h_ps',p1,sc1(k));
end
plot(sc1,hc1,'k','LineWidth',2)
text(s1+0.1,h1,'1')
text(s2+0.1,h2,'2')
text(s3,h3-100,'3')
text(s4,h4+200,'4')
title('ENTHALPY VS ENTROPY PLOT')
xlabel('ENTROPY (S) KJ/KGK')
ylabel('ENTHALPY (H) KJ/KG')
legend('SATURATION CURVE','Location','northwest')
% Displaying Results
disp(' DISPLAYING RESULTS');
fprintf('At State Point 1 \n');
fprintf('p1: %8.3f bar \n', p1);
fprintf('T1: %8.3f C \n', T1);
fprintf('h1: %8.3f KJ/kg \n', h1);
fprintf('s1: %8.3f KJ/kgK \n', s1);
fprintf('At State Point 2 \n');
fprintf('p2: %8.3f bar \n', p2);
fprintf('T2: %8.3f C \n', T2);
fprintf('h2: %8.3f kJ/kg \n', h2);
fprintf('s2: %8.3f kJ/kgK \n', s2);
fprintf('x2: %8.3f \n', x2);
fprintf('At State Point 3 \n');
fprintf('p3: %8.3f bar \n', p3);
fprintf('T3: %8.3f K \n', T3);
fprintf('h3: %8.3f kJ/kg \n', h3);
fprintf('s3: %8.3f kJ/kgK \n', s3);
fprintf('At State Point 4 \n');
fprintf('p4: %8.3f  /', p4);
fprintf('T4: %8.3f K \n', T4);
fprintf('h4: %8.3f KJ/kg \n', h4);
fprintf('s4: %8.3f kJ/kgK \n', s4);
fprintf('Turbine Work: %8.3f kJ/kg \n', wt);
fprintf('Pump Work: %8.3f kJ/kg \n', wp);
fprintf('Wnet: %8.3f kJ/kg \n', wnet);
fprintf('Efficiency: %8.3f Percent \n ', therm_eff);
fprintf('SSC: %8.3f kJ/kWh', ssc);