Natural convection in a trapezoidal enclosure filled with a porous medium

A numerical study of the steady natural convection heat transfer within an inclined trapezoidal enclosure filled with a fluid-saturated porous medium is presented in this paper. The top cylindrical surface of the enclosure is cooled and the bottom cylindrical surface is heated. The remaining two non parallel plane sidewalls of the enclosure are adiabatic. The Darcy and ener gy equation tin nondimensional stream function and temperature formulation) are solved numerically using the Alternative Direction Implicit (ADI) fini te-difference method. Flow and heat transfer characteristics (stream lines, isotherms and average Nusselt numbers) are investigated for a wide range v alues of the Rayleigh number, inclined angle and cavity aspect ratio. The p resent results are compared with those reported by J.P, Caltagirone (J. Flu id Mech. 76 (1976) 337) for natural convection in a porous medium bounded b y two concentric horizontal cylinders. It was found that these results are in excellent agreement. (C) 2000 Elsevier Science Ltd. All rights reserved.