MATLAB: 3D Fem pde inhomogeneous geometry

Question

Dear Matlab community,

I wish to perform 3D thermal simulation using the pde toolbox (which works amazingly by the way). I work with a open source software to make my STL file.

I wish to solve my pde on an inhomogeneous system. For instance two domains with different thermal conductivities. If I have been able to solve this problem on a uniform system, I do not know how to define two geometric subdomains.

My question is the following. Can I import two different geometries (different STL loading) and merge them to form an inhomogeneous system? Or should I define this system on my STL-generating software? In the latter case, is there a software that you recommend?

I thank you all for your time

Best regards

Nicolas

Answer 1

I am sorry, but currently there is no way to do exactly what you want. The current geometry creation tools do not permit 3-D subdomains.

That said, you might be able to fake the problem by carefully defining nonconstant coefficient functions that take appropriate values in the regions you like. This is not the same as having real subdomains, because the mesh is not going to respect your desired geometry, but for a relatively fine mesh it might not matter too much. And yes, it is quite difficult in general to define the coefficient functions this way, you will have to do some work.

Alan Weiss

MATLAB mathematical toolbox documentation