Numerical simulation and theoretical investigation of fluid flow and heat transfer in porous media/fluid coupled areas have been widely studied in recent years. Few researches are focused on compressible gas flow in porous media/fluid coupled areas.The unified governing equations for the fluid and porous media are used to describe the compressible flow in porous media/fluid coupled areas. A method to decide the source terms for flow in porous media is also presented. As an example

a detailed numerical simulation of compressible gas flow in a straight round pipe with porous media/fluid coupled areas and backward-facing and forward-facing steps are carried out and the computational results coincide with the experimental data.