A macroscopic momentum equation for flows in porous media of dual structure

A macroscopic momentum equation for flows through porous media of dual stru cture was derived by integrating Navier-Stokes equations over a local contr ol volume. The smaller scale-fluid motions associated with the "secondary" structure were modeled first. Then, the larger scale-fluid motions within t he "primary" structure were modeled successively, to obtain the macroscopic momentum equation for porous flows through porous media of dual structure. Both pressure measurement and numerical experiment conducted for the flows in porous media of dual structure substantiate the validity of the present macroscopic momentum equation.