Project 2 - Rankine cycle Simulator
To Simulate basic Rankine cycle
Objective
- Creating a rankine cycle simulator using Matlab or Octave. Calculating the state points of the Rankine cycle base on the input.
- then plotting the coresponding T-s and h-s plots for the given set of inputs.
Rankine Cycle:
The process widely used by the power plants such as coal fire power plant or nuclear reactor. in this mechanism a fule is used to produce heat within a boiler converting water into stream which expands through a turbine producing useful work.
Different processes are
1-2: isentropic expansion in the turbine
2-3: isobaric heat rejection by the condenser
3-4: isentropic comperssion in the pump
4-1: isobaric heat addition by the boiler
Given inputs
CODE:
clear all
close all
clc
% 1-2 : Isentropic Expansion in the turbine
% 2-3 : Isobaric Heat Rejection by the condenser
% 3-4 : Isentropic Compression in the pump
% 4-1 : Isobaric Heat Addition by the boiler
% Initialization input values of the variables
P1 = input('Enter the pressure at the inlet of the Turbine (in bar) : ');
T1 = input(['Enter the temperature at the inlet of the Turbine(in degree C) : ']);
P2 = input('Enter the pressure at the inlet of Condenser(in bar) : ');
t = linspace(0,373.15,200);
disp(' ')
% Calculating And Displaying the values of P,T,h,s for each state using 'XSteam' library
% At state point 1
h1 = XSteam('h_pT',P1,T1); % Enthalpy at point 1
s1 = XSteam('s_pT',P1,T1); % Entropy at point 1
hl1 = XSteam('hL_p',P1); % Saturated liquid enthalpy
hg1 = XSteam('hV_p',P1); % Saturated vapour enthalpy
sl1 = XSteam('sL_p',P1); %Saturated liquid entropy
sg1 = XSteam('sV_p',P1); % Saturated vapour entropy
Tsat1 = XSteam('Tsat_p',P1); % Saturation temperature
% At state point 2
s2 = s1;
sl2 = XSteam('sL_p',P2);
sg2 = XSteam('sV_p',P2);
d = (s2-sl2)/(sg2-sl2); % d is dryness fraction
hl2 = XSteam('hL_p',P2);
hg2 = XSteam('hV_p',P2);
h2 = hl2 + d*(hg2-hl2);
T2 = XSteam('T_ph',P2,h2);
Tsat2 = XSteam('Tsat_p',P2);
% At state 3
h3 = hl2;
s3 = sl2;
P3 = P2;
T3 = T2;
% At state 4
s4 = s3;
P4 = P1;
h4 = XSteam('h_ps',P4,s4);
T4 = XSteam('T_ps',P4,s4);
% Work and efficiency Calculations
% Work done by turbine
W_turbine = h1 - h2;
% Work done by pump
W_pump = h4 - h3;
% Net work dome
W_net = W_turbine - W_pump;
% Thermal efficiency
therm_eff = (1 - ((h2 - h3)/(h1 - h4)))*100;
% Back work ratio
back_wr = W_pump/W_turbine;
% Specific Steam Conductivity
ssc = 3600/W_turbine;
% Plotting Of Different curevs
% Plotting T-s graph
figure(1), clf
hold on
% Saturation curve
for i = 1:length(t)
plot(XSteam('sL_T',t(i)),t(i),'g')
plot(XSteam('sV_T',t(i)),t(i),'g')
end
% Cycle
plot([s1 s2],[T1 T2],'linewidth',2)
text(s1,T1,'1','FontSize',15)
if d > 1
T3 = Tsat2;
plot([s2 sg2 s3 s4],[T2 Tsat2 T3 T4],'linewidth',2)
T2 = Tsat2;
text(s2,T2,'2','FontSize',15)
text(s3,T3,'3','FontSize',15)
else
plot([s2 s3 s4],[T2 T3 T4],'linewidth',2)
text(s2,T2,'2','FontSize',15)
text(s3,T3,'3','FontSize',15)
end
n = linspace(T1,T2,500);
for i = 1:length(n)
plot(XSteam('s_pT',P1,n(i)),n(i),'.','linewidth',2)
end
plot([sl1 sg1],[Tsat1 Tsat1],'linewidth',2)
text(sl1,Tsat1,'4','FontSize',15)
xlabel('Entropy(kJ/kg-K)')
ylabel('Temperature(k)')
title('T-s graph')
% h-s graph
figure(2), clf
hold on
% Saturation curve
for i = 1:length(t)
plot(XSteam('sL_T',t(i)),XSteam('hL_T',t(i)),'r.')
plot(XSteam('sV_T',t(i)),XSteam('hV_T',t(i)),'r.')
end
% Cycle
plot([s1 s2 s3 s4 s1],[h1 h2 h3 h4 h1],'linewidth',2)
text(s1,h1,'1','FontSize',15)
text(s2,h2,'2','FontSize',15)
text(s3,h3,'3','FontSize',15)
text(s4,h4+90,'4','FontSize',15)
xlabel('Entropy(kJ/kg-K)')
ylabel('Enthalpy(kJ/kg)')
title('h-s graph')
%Displaying the results in the command window
%AT STATE POINT 1:
disp('At state point 1: ')
fprintf('P1 = %.2f bar n',P1)
fprintf(['T1 = %.2f' char(176) 'C n'],T1)
fprintf('h1 = %.2f kJ/kg n',h1)
fprintf('s1 = %.2f kJ/kgK n',s1)
disp(' ')
%AT STATE POINT 2:
disp('At state point 2: ')
fprintf('P2 = %.2f bar n',P2)
fprintf(['T2 = %.2f' char(176) 'C n'],T2)
fprintf('h2 = %.2f kJ/kg n',h2)
fprintf('s2 = %.2f kJ/kgK n',s2)
disp(' ')
%AT STATE POINT 3:
disp('At state point 3: ')
fprintf('P3 = %.2f bar n',P3)
fprintf(['T3 = %.2f' char(176) 'C n'],T3)
fprintf('h3 = %.2f kJ/kg n',h3)
fprintf('s3 = %.2f kJ/kgK n',s3)
disp(' ')
%AT STATE POINT 4:
disp('At state point 4: ')
fprintf('P4 = %.2f bar n',P4)
fprintf(['T4 = %.2f' char(176) 'C n'],T4)
fprintf('h4 = %.2f kJ/kg n',h4)
fprintf('s4 = %.2f kJ/kgK n',s4)
disp(' ')
fprintf('Work done by turbine = %.2f kJ/kg n', W_turbine)
fprintf('Work done by pump = %.2f kJ/kg n', W_pump)
fprintf('Net work done = %.2f kJ/kg n', W_net)
fprintf('Thermal efficiency = %.2f %% n', therm_eff)
fprintf('Back-work ratio = %f n', back_wr)
fprintf('Specific Steam Conductivity = %.2f kg/kWh n',ssc)Output result & workspace:
T-s plot:
h-s Plot:
Code explanation:
Step 1: In this step the values of P2, T1, P2 are given. Using "linspace" command we have created the temperature value array "t".
Step2: Here using the provided "Xsteam liabrary value of various physical parameters like enthalpy, entropy, saturation liquid/vapour, saturated temp at 4 state points were calculated.
Step3: Like wise previously the state points 3 & 4 were calculated.
Step4: This step the basic work done using the equaitons are calculated.
Step5: Ploting T-s cuve, using "Xsteam" library function T-s graph is plotted at different temperature array values. then along with the state points the curve was plotted.
Step6: Simliarly h-s curve is plotted, using the "Xstream" libarary function to plot the h-s curve at different temperature array values, along with the state points the curve was plotted.
Step7: In this step the values of the physical parameters at the state points were displayed in the output window. it is repeated for all the four defining state points in same type.
Step8: The final result W_net, W_turbine, W_pump, back_wr, ssc, therm_eff were printed.
Errors faced:
-forget to close the for loop, like that i have faced more
To over those error i have again and again understand the code definition
Referances:
https://energyeducation.ca/encyclopedia/Rankine_cycle
https://en.wikipedia.org/wiki/Rankine_cycle
https://www.e-education.psu.edu/eme812/node/708