Abstract
Heat rejection augmentation in a ventilated cavity filled partially with a porous medium is studied numerically using the finite-element method. Analyses were performed in a mixed convection heat transfer regime. Results were obtained using various pertinent dimensionless parameters; namely; the effects of the solid-to-fluid thermal conductivity ratio (1-100), Darcy number (10 super(-3-10) super(-)6), Richardson number (0.01-10), location of the porous layer (0.1-0.9), and width of the porous layer (0.1-0.9) on the streamlines, and the isotherms, average Nusselt number and the bulk average fluid temperature are analyzed in this investigation. The generalized model of the momentum equation, which is also known as the Forchheimer-Brinkman extended Darcy model, is employed in modeling the fluid motion inside the porous layer. In addition, the local thermal equilibrium condition was assumed to be valid for the range of the thermophysical parameters considered in the present investigation. The results of this investigation reveal that the location and width of the porous layer play a significant role in the pattern of the streamlines and isotherms within the enclosure. Moreover, the average Nusselt number and the bulk average fluid temperature are found to increase as the porous layer moves toward the exit port. However, the Nusselt number is found to decrease while the average temperature increases as the width of porous layer increases. Finally, the contribution of the conduction and convection heat transfer regimes to the overall energy transport within the enclosure revealed some interesting optimization scenarios.