A macroscopic turbulence model for flow in a porous medium

A complete set of macroscopic two-equation turbulence model equations has b een established for analyzing turbulent flow and heat transfer within porou s media. The volume-averaged transport equations for the mass, momentum, en ergy, turbulence kinetic energy and its dissipation rate were derived by sp atially averaging the Reynolds-averaged set of the governing equations. The additional terms representing production and dissipation of turbulence kin etic energy are modeled introducing Two unknown model constants, which are determined from a numerical experiment using a spatially periodic array. In order to investigate the validity of the present macroscopic turbulence mo del, a macroscopically unidirectional turbulent flow through an infinite ar ray of square rods is considered from both micro- and macroscopic-views. It has been found that the streamwise variations of the turbulence kinetic en ergy and its dissipation rate predicted by the present macroscopic turbulen ce model agree well with those obtained from a large scale microscopic comp utation over an entire field of saturated porous medium.