Second Law Approach for Turbulent Flow in an Annular Duct Partly Filled with a Porous Substrate

The paper is aimed at investigating the turbulent flow and heat transfer characteristics in an annular duct partly filled with a porous medium. A modified k-epsilon model for approximating the Forchheimer term in the equations of turbulent kinetic energy and dissipation rate is developed by time-averaging the general macroscopic transport equations. This model accounts for the second order approximation in the Forchheimer term. This higher order term leads to a better description of the turbulent effects of the Forchheimer term in the flow through the porous medium. A second law approach, based on the entropy generation is used, in order to find the compromise between hydrodynamics and thermal performances.