Hello everyone, I am a biology student, and due to the recent pandemic, I had to shift my project to a simulation study. I am unsure of how to go about modeling a 2D rectangular column whose entire surface is porous (sand). I just want to pass water at the inlet and calculate the outlet velocity. I was able to learn geometry and meshing part but I have no clue how to designate the entire surface as a sand porous media. Please provide me some insight on how I can approach this. 


P.S. I know the effective sand diameter, porosity, and permeability of the filter through experimental results. I have also tried to follow a few tutorials online but either all of them used a gas fluid and never used sand as the porous media.