I want to flow water parallel to a porous membrane (top chamber) and track how much fluid passes through it over time (bottom chamber). The problem I am having is not being able to isolate flow to the top chamber only. I tried to split the part such that the top chamber is only in the flow region but I get infinite flow volume errors. Because I am on a university license apparently I cannot link the project (make it public).
Hey @izaiah210 ,
You can still share your project with support. See this. Please paste the project URL here once you enable the ‘share with support’ option for us to take a look at the model.
I don’t know if I fully understand what you mean. But if you want to see the water passing through the porous media the entire region (where water can exist, i.e. top as well as bottom chamber) should be included as part of a single flow region. With a single-phase flow simulation, the entire region defined is always already filled with water. From what I understand, in your case, initially you would like the top chamber to be water and the bottom chamber to be air and then you would like to see how water passes through the porous media down into the bottom chamber starting at time ‘t’. Is that correct?
Technically speaking, this would be a multiphase simulation. The porous media advanced concept is not available with a multiphase simulation. This would have to be modelled as part of the CAD and would also have to be finely meshed to account for the pores. That does not make a lot of sense to do, honestly. An alternative could be to model the entire flow region as a single phase of water and run a simple incompressible simulation through the detailed model to see how flow behaves as it flows through it.
Let us know what you think! 
Best,
Satvik
Thank you for the suggestions! I will try these out and report back.