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Topic: Pdepe
Replies: 5   Last Post: Mar 26, 2013 3:55 AM

 Messages: [ Previous | Next ]
 Torsten Posts: 1,631 Registered: 11/8/10
Re: Pdepe
Posted: Mar 25, 2013 11:05 AM

"Igor" wrote in message <kipm7d\$61d\$1@newscl01ah.mathworks.com>...
> I cannot provide the whole code, just key components:
>
> I have system of 16 eq like this(only first rows) for steady state:
> .....
> function [c,f,s] = pdex14pde....
> c = ones(NumVars,1);%c
> f = [(D_bio+D_O2)*DuDx(1)-w*u(1);....
> s = [(BC0_O2-u(1))*alfax + (-0.25*R8-2* 1.5*R21 - 0.5*R22) - R1*F;... %w,R,alfax-some constant coef.
> ..........
> function u0 = pdex1ic(~)
> global NumVars;
> u0 = zeros(NumVars,1);%u0
> ...........
> function [pl,ql,pr,qr] = pdex1bc(~,ul,~,ur,~)
> pl = [ul(1)-BC0_O2;...
> ql = [0;1;....
> pr = [w*ur(1);...
> qr = ones....
>
> This code takes 300 sec for calculation.
>
> But then I make some BC0_OM1=(360*cos(t*(2*pi))+360) it takes hours.
>
> Maybe it will help,
> Igor

I doubt that a steady-state solution for your problem exists if a boundary condition depends on time.
Or did I misunderstand something ?

Best wishes
Torsten.

Date Subject Author
3/23/13 Nasser Abbasi
3/25/13 Torsten
3/26/13 Torsten