i don't find the error
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i have this system:
dC/dt+(u/epsilon)*dC/dz-Dl*(d^2 C)/(dz^2 )+((1-epsilon)/epsilon)*(rhos/rhof)*dq/dt=0 ;
dq/dt=K*a*(q-Keq*C )
the initial and boundary conditions are:
t=0, C=C0, z>0
t=0, q=q0, z>0
z=0, (u/epsilon)* C-Dl*dC/dz=0, t>0
z=L, dC/dz=0, et dq/dz=0 ;t>0
i wrote this algorithm but i have an error that i don't find it:
function vasco
m=0;
z=linspace(0,30);
t=[ 0 50 100 150 200];
sol = pdepe(m,@pdexpde,@pdexic,@pdexbc,z,t);
C = sol(:,:,1);
q = sol(:,:,2);
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;
Dl=4.7E-5;
keq=16.86;
A=Ki*a*(C(2)-(keq*C(1)));
B=((1-epsilon)/epsilon)*(rhos/rhof)*A;
g=[1; 1];
f=[Dl.*DCDz; 0];
s=[((-u)/epsilon).*DCDz-B; A];
function u0 = pdexic(z)
c0=0.0015;
q0=2.53E-2;
u0 = [c0; q0];
% -------------------------------------------------------------------------
function [pl,ql,pr,qr] = pdexbc(zl,Cl,zr,Cr,t)
q0=2.53E-2;
Dl=4.7E-5;
epsilon=0.45;
u=0.098;
pl = [(u/epsilon)*Cl(1); Cl(2)-q0];
ql = [-1; 0];
pr = [0; 0];
qr = [(1/Dl); 0];
this is the first time that i use matlab so this program is true for this type of système??
thanks in advance for your help!!! please it's urgent
5 Comments
Answers (1)
Jan
on 11 May 2011
Faster than asking here is using the debugger:
dbstop if error
Then Mtlab stops, when the error occurs and you can inspect the current values of the variables to find out, what causes the problem.
4 Comments
Andrew Newell
on 11 May 2011
Also, unless you have a really old version of MATLAB, you should be able to click on a link in the error message to take you to the line where the error was flagged.
Sean de Wolski
on 11 May 2011
Excellent thank you! I'd always wondered that; since I rarely close MATLAB I find a residual dbstop if error messing with me a day or two after needing it.
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