Dear users, I want use Fluent to mdel heat transfer and fluid flow in channel containing a porous block (i.e.: channel partielly filled with a porous media). I can't sepcify the porous zone and particulary the interface fluid-porous region, I need your help

Why can't you specify a porous region? I believe that you can select the boundary condition of the surface to be a porous media. Look at tge b.c. panel, and see if it is an option. Tell me what you find.