Study of Forced Convection in a Pipe Partially Filled with a Porous Medium

The objective of the present work was to perform a detailed numerical study of laminar fully developed forced convection in a pipe partially filled with a porous medium. The Brinkman-Forchheimer-extended Darcy model is adopted for the porous matrix region, which is attached to the pipe wall and extends inward, toward the centerline. The effects of the Darcy number, Da, the thickness of a porous layer, S, and the thermal conductivity ratio, R-k, are investigated. The results showed that as the thickness of the porous layer increases or the Darcy number decreases, the pressure drop grows. It was found that the dependence of the Nusselt number Nu on S is not straightforward. For a high Rk, the Nusselt number increases monotonically with increasing S while for a low Rk a minimum exists in the distributions. The obtained results show that increasing either the Darcy number or the thermal conductivity of the porous material improves the convective heat transfer. Further, for highly permeable and conducting porous media, it may not be necessary to fill the pipe cross section completely to attain maximum heat transfer.