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chris_j_meyer June 11, 2013 06:58

Anisotropic, implicit momentum source term
Hi All

Will not bore you with the details, but I am adding a momentum source term that is anisotropic. To do this explicitly is quite easy as a volVectorField with the sources can just be added to the U-equation. For an implicit formulation the following can be used and added to the U-equation:

fvm::Sp(a, U)

However, "a" can at best be a volScalarField and hence the source will be locally isotropic. Is there any way in which I can add different implicit source terms to the momentum equations in the three coordinate directions?


Lieven June 11, 2013 10:56

Hi Chris,

Have a look at the implementation of the porous media source term. I think this is what you are looking for.



ski July 18, 2013 18:42

I'd like to do this too..

Issue is that it appears to be using Jacobi method to solve, which tends to give poor convergence rates. Anyone have any experience on this?

mateusps July 25, 2016 16:11

Did anyone find a way to program an implicit anisotropic source???
Hello y'all,

I have the same problem: how to program an anisotropic implicit source in the momentum equation?

fvm::Sp simply does not accept a tensor as coefficient (fvm::Sp(tensor,vector) does not seem to be implemented).

Did anyone find a way?


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