Using Matlab pdepe solver

I want to simulate performance of a hybrid thermal energy storage system with a latent and sensible heat storage sections, but i am new to Matlab. I have developed a code for transient heat transfer in the latent heat storage section, between a heat transfer fluid and the PCM capsules. I am seeking for assistance on how to include a similar code for the sensible section. The conditon for linking the two sections is that, the HTF outlet temperature from the latent section is equal to the HTF inlet temperature for the sensible section. Please help on how I can link the two codes.

Answer 1

[Gyan Vaibhav]

Hi luckywell,

I understand that you are trying to use the values you get in the LHS section of your code in to the SHS section during simulation. If you could have provided the code I could have been able to suggest you better, however here are a few tips that might help.

1. Using functions, you can seperate each of the sections in to seperate function and make a call to both the functions return the values as requirement from one which can be used in the other depending on your system configuration. https://www.mathworks.com/help/matlab/ref/function.html
2. You can simulate and modulate physical systems using "Simscape". Here is an example it might help provide some more information.

https://www.mathworks.com/help/hydro/ug/BuildingThermalManagement.html

https://www.mathworks.com/help/hydro/examples.html?category=heating-and-cooling-examples&s_tid=CRUX_topnav

Hope this helps.

Thanks

Gyan

[luckywell seyitini]

Thanks very much Gyan for the advice and suggested options. here is the pdepe code for the latent section:

function pdex4

m = 1;

x = [0:0.02:0.3];

t = [0:1:30];

sol = pdepe(m,@pdex4pde,@pdex4ic,@pdex4bc,x,t);

u1 = sol(:,:,1);

u2 = sol(:,:,2);

figure

surf(x,t,u1)

title('u1(x,t)')

xlabel('Distance x')

ylabel('Time t')

figure

plot(x,u1(end,:))

title ('Variation of HTF temperature')

xlabel('Distance x')

ylabel('Temperature T')

figure

plot(x,u2(end,:))

title('Variation of PCM temperature')

xlabel('Distance x')

ylabel('Temperature T')

figure

imagesc(x,t,u1); colormap hot; colorbar; grid on

title('Temperature distribution in HTF');

xlabel('Distance x')

ylabel('Time t')

figure

imagesc(x,t,u2); colormap hot; colorbar; grid on

title ('Temperature distribution in PCM');

xlabel('Distance x')

ylabel('Time t')

figure

surf(x,t,u2)

title('u2(x,t)')

xlabel('Distance x')

ylabel('Time t')

% --------------------------------------------------------------

function [c,f,s] = pdex4pde(x,t,u,DuDx)

c = [1138089.525; 1247264.07];

f = [DuDx(1); DuDx(2)];

y = u(1) - u(2);

U = 0.01685;

h = 80476.1032;

F = -U*DuDx(1)-h*y;

G = h*y;

s = [F; G];

% --------------------------------------------------------------

function u0 = pdex4ic(x);

u0 = [170;25];

% --------------------------------------------------------------

function [pl,ql,pr,qr] = pdex4bc(xl,ul,xr,ur,t)

pl = [ul(1)-170; 0];

ql = [0; 1];

pr = [0; ur(2)-25];

qr = [1; 1];