Porous media and adjacent BCs
 

Hi Experts,

I am modeling a housing which contains a heat exchanger, which I have modeled as porous medium. The HE is completely inside the housing. Now problem is that HE allows flow in one direction only (say x direction). So I made the X side walls of the porous medium as 'interior' BCs and remaining side walls as 'walls' with one side as porous medium and other side as fluid. The problem do not converge. But it converges as soon as I make all BCs as 'interior'. What could be the problem? Do porous media modeling allows two different BCs at interface?

Yes, porous media does allow two different BCs at interface, I have done the same few times already, never give me problem.
But I can't understand your problem, what you mean by 'So I made the X side walls of the porous medium as 'interior' BCs and remaining side walls as 'walls' with one side as porous medium and other side as fluid.'?
Usually, I defined the both surfaces at x-direction as interior, other surfaces as wall, meanwhile the volume as porous medium,
Is it same as yours?
Then is shouldn't be the problem.