COMSOL Forums: help on a hard question:1d but two variables

Re: help on a hard question:1d but two variables

Wed, 17 Mar 2010 11:57:42 +0000

Dont know about the convergence or even the existence of solution but if I had to solve something like that, I will use a 2d pde on a rectangle domain , the variable being z the other q.
calculate D as a projection coupling variable on the z axis and write your first equation as a pde on the rectangle . Of course the boundary conditions will need to be properly written.
Good luck
jf

Re: help on a hard question:1d but two variables

Wed, 17 Mar 2010 11:48:40 +0000

Is there anyone who is willing to help me solve this problem? Or just give me some hints on how to solve it. Thanks!

help on a hard question:1d but two variables

Tue, 16 Mar 2010 08:37:52 +0000

Hello, everyone:

I am studying an electromagnetic model:

-d/dz(D(z)d/dz)C(z,q) + D(z)*q^2*C(z,q) =1
where
1/D(z)=integral(dq*q*C).

z is a space variable, and q is not a space variable(frequency value). So it is a 1D question in fact but there are two variables in the equation.

Is it possible to design two sub-domains, one for z and the other for q?

Thanks a lot!

Hao