Numerical simulation of turbulent flow and heat transfer in a channel partially filled with a porous media

In the present study, turbulent flow and heat transfer through a partially porous channel is investigated numerically. Two common arrangements of a porous layer in the channel are considered; central arrangement and boundary arrangement. Different values of the porous layer thickness as well as Darcy number are studied for both arrangements. The peak of the turbulent kinetic energy takes place at the porous/fluid interface. A special thickness exists in which the Nusselt number is maximum for the central arrangement and minimum for the boundary arrangement, due to channeling effect. For the central arrangement, the thickness which yields the highest Nusselt number is found to be 0.83, 0.88 and 0.9 for Darcy numbers 10−2, 10−3 and 10−4 respectively. Also, for the boundary arrangement, the Nusselt number takes on its minimum value for thicknesses between 0.6 and 0.7, depending on the value of the Darcy number; the smaller is the Darcy number, the larger is the value of thickness at which the minimum Nusselt number occurs. Besides, for both arrangements, an optimum thickness of the porous layer is defined, taking into account the Nusselt number together with a reasonable pressure drop. Hence an effective Nusselt number has been employed and via its values, an optimum thickness of the porous layer is proposed.

► Turbulent heat transfer through a partially porous channel is investigated numerically.
► The peak of the turbulent kinetic energy takes place around the porous/fluid interface.
► The pressure drop of the central configuration is higher than that of the boundary one.
► Optimum porous thickness in turbulent flow is different from that of laminar flow.