Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.


Torsten
Posts:
1,639
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_O2u(1))*alfax + (0.25*R82* 1.5*R21  0.5*R22)  R1*F;... %w,R,alfaxsome 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 steadystate solution for your problem exists if a boundary condition depends on time. Or did I misunderstand something ?
Best wishes Torsten.



