Project 2 - Rankine cycle Simulator

clear all
close all
clc

% Rankine cycle simulator
fprintf('Rankine Cyclen')
fprintf('1-2 is Isentropic Expansion in Turbinen') 
fprintf('2-3 is constant pressure heat removaln')
fprintf('3-4 is Isentropic Compression in Pump n')
fprintf('4-1 Constant pressure Heat addition in Boilern')

% Entering the input data for calculation of state points
p1 = 50;     %Pressure at Turbine Inlet 
T1 = 500;    %Temperature at Turbine Inlet
p2 = 5;      %Pressure at Condenser

% Taking data from Xsteam file for State point 1
h1=XSteam('h_pT',p1,T1);           % Enthaply at pressure and Temp 1
s1 = XSteam('s_pT',p1,T1);         % Entropy at pressure and Temp 1


% Taking data from Xsteam file for State point 2
s2= s1;                     % Because of Isentropic Expansion
sf2 = XSteam('SL_p',p2);    % Saturated liquid entropy at pressure 2
sg2 = XSteam ('SV_p',p2);   % Saturated vapour entropy at pressure 2
x2 = (s2-sf2)/(sg2-sf2);    % Vapour Fraction at state point 2
hf2 = XSteam('hL_p',p2);    % Saturated liquid Enthalpy at pressure 2
hg2 = XSteam('hV_p',p2);    % Saturated liquid Enthalpy at pressure 2
h2 = hf2 + (x2*(hg2-hf2));  % Enthalpy at state point 2


% Taking data from Xsteam file for state point 3
p3= p2;                  % Constant Pressure heat removal process
s3 = XSteam('sL_p',p3);  % Saturated liquid entropy at Pressure 3
h3 = XSteam('hL_p',p3);  % Saturated liquid Enthalpy at Pressure 3

% Taking data from Xsteam file for State point 4
s4 = s3;   % Isentropic Compression process
p4 = p1;   % Constant Pressure heat rejection

% work done in Turbine for the Rankine cycle
W_T = h1-h2;             % work done required for pump
v3 = XSteam('vL_p',p3);  % Saturated Liquid Vapour at pressure 3
W_P = v3*(p4-p3)*100;    % Work done for pump
h4 = h3 - W_P;           % Enthalpy at State point 4

% Network done for Rankine Cycle 
W_net= W_T-W_P;

% Heat Addition to System
Q_in= h1-h4;

% Heat Rejection from System
Q_out= h2-h3;

% Thermal Efficiency of Rankine Cycle
T_eff= (W_net/Q_in)*100;

% specific steam consumption = (Mass flow rate / Net work done)
Sp_S= (3600/W_net);

% Calculation of Temperature at All state Point 2, 3 and 4
T3 = XSteam('Tsat_p',p3);      % Saturation Temperature at Pressure 3
T2 = T3;                       % Becuase of Constant Pressure Heat addition
Cp4 = XSteam('Cp_ps',p4,s4);   % Specific isobaric heat capacity
Cv4 = XSteam('Cv_ps',p4,s4);   % Specific isochoric heat capacity
k = Cp4/Cv4;
T4 = T3/((p3/p4)^((k-1)/k));   % Temperature at State point 4


% Calculation of other constant for saturated liquid and vapour
T6 = XSteam('Tsat_p',p1);  % Saturated Temperature at Pressure 1
s5 = XSteam('sL_p',p1);    % Saturated Liquid entropy at pressure 1
s6 = XSteam('sV_p',p1);    % Saturated Vapour entropy at Pressure 1
h5 = XSteam('hL_p',p1);    % Saturated Liquid Enthalpy at Pressure 1
h6 = XSteam('hV_p',p1);    % Saturated Vapour Enthalpy at pressure 1
T5  = T6;

%Plotting for Saturation Line
T=linspace(1,560,1000);
for i=1:length(T)
    sf(i) = XSteam('sL_T',T(i)); 
    % Saturated Liquid Entropy
    sg(i)= XSteam('sV_T',T(i)); 
    % Saturated Vapour Entropy
    hf(i)=XSteam('hL_T',T(i));
    % Saturated Liquid Enthalpy
    hg(i) = XSteam('hV_T',T(i));
    % Saturated Vapour Enthalpy

end

% Plotting T-S Diagram for Rankine Cycle
figure(1)
hold on
plot (sf,T,'color', 'b', 'linewidth', 2)
plot (sg, T, 'color', 'b', 'linewidth', 2)
plot([s1 s2], [T1 T2], 'color', 'r', 'linewidth', 3)
plot([s2 s3], [T2 T3], 'color', 'r', 'linewidth',3)
plot([s3 s4],[T3 T4], 'color', 'r', 'linewidth',3)
plot([s4 s5], [T4 T5], 'color', 'r', 'linewidth',3) 
plot([s5 s6], [T5 T6], 'color', 'r', 'linewidth', 3)

s_1 = linspace(s6,s1,1000); 
for j=1:length(s_1)
    TC(j)=XSteam('T_ps',p1,s_1(j));

end

plot(s_1,TC,'color','r','linewidth',3)
text(s1+0.1,T1,'1') 
text(s2+0.1,T2,'2')
text(s3,T3-20,'3') 
text(s4,T4+20,'4')
title('Temperature Vs Entropy')
xlabel('Entropy (kj/kg-k)')
ylabel('Temeperature (Deg. Celcius)')
legend('Saturation Curve')

% Plotting H-S Diagram for Rankine Cycle
figure(2)
hold on
plot(sf, hf, 'color', 'b', 'linewidth',2)
plot(sg, hg, 'color', 'b', 'linewidth',2) 
plot([s1 s2], [h1 h2], 'color', 'r', 'linewidth', 3)
plot([s2 s3], [h2 h3], 'color', 'r', 'linewidth', 3) 
plot([s3 s4], [h3 h4], 'color', 'r', 'linewidth', 3)

hc = linspace(h4,h5,100);
for k = 1:length(hc) 
    s_c(k)=XSteam('s_ph',p1,hc(k));

end

plot(s_c,hc,'color','r','linewidth',3) 
plot([s5 s6],[h5 h6],'color','r','linewidth',3)

for l = 1:length(s_1)
    h_c(l) = XSteam('h_ps',p1,s_1(l));

end

plot(s_1,h_c,'color','r','linewidth',3)
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')
xlabel('Entropy (kj/kg-k)')
ylabel('Enthalpy (KJ/Kg)')
legend('Saturation Curve')

% Displaying Results in Command window disp('Results of Rankine Cycle')
fprintf('At state point 1ttttt') 
fprintf('At state Point 2n')
fprintf('P1 = %10f in Bartttt',p1);
fprintf('P2 = %10f in Barn',p2); 
fprintf('T1 = %11f in Deg.Celciustt',T1);
fprintf('T2 = %11f in Deg.Celciusn',T2);
fprintf('H1 = %12f in KJ/Kgttt',h1); 
fprintf('H2 = %12f in KJ/Kgn',h2);
fprintf('s1 = %9f in KJ/Kg-kttt',s1); 
fprintf('s2 = %9f in KJ/Kg-kn',s2);
fprintf('n')

fprintf('At state point 3ttttt')
fprintf('At state Point 4n')
fprintf('P3 = %10f in Bartttt',p3);
fprintf('P4 = %10f in Barn',p4);
fprintf('T3 = %11f in Deg.Celciustt',T3);
fprintf('T4 = %11f in Deg.Celciusn',T4);
fprintf('H3 = %12f in KJ/Kgttt',h3);
fprintf('H4 = %12f in KJ/Kgn',h4);
fprintf('S3 = %9f in KJ/Kg-kttt',s3);
fprintf('S4 = %9f in KJ/Kg-kn',s4);
fprintf('n')

fprintf('Turbine Work Done = %14f in KJ/Kgn',W_T)
fprintf('Pump Work Done = %15f in KJ/Kgn',W_P)
fprintf('Net Work Done = %17f in KJ/Kgn',W_net) 
fprintf('Thermal Efficiency = %13f in percentn',T_eff)
fprintf('Sp.Steam Consumption = %f in KJ/Kwn',Sp_S)

​

• The creation of the Rankine cycle simulator starts with some input values which are required to calculate the other state point in the cycle eventually.
• The Rankine cycle process is displayed in the command window and then inputs are entered which are inlet pressure for the turbine, the temperature at the turbine inlet, and pressure at the condenser.
• Then we are using the XStream function file for reading state points. First, we get the value of enthalpy and entropy at state point 1 from the XStream function file.
• As process from 1-2 is isentropic compression the entropy at point 1 is equal to point 2. The term '(s_pT, p1, T1)' refers to entropy at pressure and temperature point 1.
• The term 'sg' and 'st' is referred to saturated liquid and saturated vapor entropy respectively. This value is used to calculate other functions according to mathematical relations.
• Similarly, other points are taken from the XStream function file which is necessary to calculate other parameters. After that work done in the turbine and pump is calculated for further getting the network done Rankine cycle.
• After calculating the net work done the efficiency of the Rankine cycle is calculated along with specific steam consumption which is steam consumed by a locomotive cylinder per unit of output of work done.
• Then temperature at each point of the cycle is calculated using input taken from the start of the program and data taken from the XStream file. Forgiven temperature ranges from lower to higher entropy points are calculated to create the T-S plot. Similarly, another for loop is used to generate the saturation curve in each plot.
• Then plotting is done respectively for T-s and H-s graph in the Rankine cycle and each state point value has been put in the command window.

• For Inlet pressure in Turbine as = 30 bar.
• Inlet temperature in Turbine = 400 deg.cel.
• Pressure in condenser = 0.05 bar.

Rankine Cycle:

• https://in.mathworks.com/matlabcentral/answers/12855-newlines-and-spaces-in-strings