resolution of PDE
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I have a system of equations:
(?C/?t)+(u/?)?C/?z+((1-?)/?)*(?s/?f)*Ki*a*(q-KéqC)=0
?q/?t=-Ki a(q-KéqC)
the initial condition is:
t=0, q=q0 and C=C0,z>0
the boundary conditions are:
z=0;C=0 and q=q0
z=L; ?C/?z=0 ,?q/?z=0
this is my program: i don't find the error so pleaaase help me. thanks in advance.
function modelediffusion
m=0;
z=linspace(0,1,26);
t=linspace(0,2,200);
sol = pdepe(m,@pdexpde,@pdexic,@pdexbc,z,t);
C = sol(:,:,1);
q = sol(:,:,2);
figure
plot(t,C(:,15))
function[g,f,s]= pdexpde(z,t,C,DCDz)
rhos=0.55;
rhof=0.385;
dp=0.03;
a=6/dp;
epsilon=0.45;
Ki=1.4E-7;
u=0.098;
Keq=16.86;
A=Ki*a*(C(2)-(Keq.*C(1)));
B=((1-epsilon)/epsilon)*(rhos/rhof)*A;
g=[1; 1];
f=[0; 0];
s=[((-u)/epsilon).*DCDz-B; A];
function C0 = pdexic(z)
c0=1.5E-3;
q0=2.53E-2;
C0 = [c0; q0];
% -------------------------------------------------------------------------
function [pl,ql,pr,qr] = pdexbc(zl,Cl,zr,Cr,t)
q0=2.53E-2;
pl = [C1(1);q0-Cl(2)];
ql = [1; 0];
pr = [0; 0];
qr = [0; 1];
5 Comments
Walter Roberson
on 8 May 2011
The question marks indicate derivative. Except the ones that appear isolate right after a "/" -- I don't know what those are.
Is KéqC a complete variable, or is it Kéq * C ?
Answers (1)
Andrew Newell
on 8 May 2011
Here is one error: in this line,
pl = [C1(1);q0-Cl(2)];
the first C1 is C followed by the numeral 1, but it should be C followed by the letter l.
Debugging note: It is a good idea to have just one command per line. That way, when you get an error message, you know which command triggered it (if not which command actually caused it).
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