Porous Media in Cylindrical Geometry

Danny B

I am modeling flow through a packed bed in a cylindrical geometry where the packed bed is in a small region on the outer wall. I have two inlets and one outlet. One inlet represents a spray located at the center of the cylinder directed towards the packed bed and the second inlet is air coming in above the spray from one of the end caps of the cylinder. The outlet is located above the porous region. I am implementing the porous media via the fluid boundary condition but my solution doesn't seem to converge realistically to where I should see a spray impacting the porous bed and a secondary flow that recirculates throughout the cylinder. Any guidance on this scenario would be greatly appreciated.