Dissimilar Heat Transfer Enhancement in Turbulent Porous–Channel Flow

Abstract

In this study, direct numerical simulations of turbulent channel flow with a porous wall have been performed to investigate the effect of the permeability on the heat and momentum transfer. The porous wall is anisotropic, consisting of many small holes in the wall-normal direction, which are introduced by the immersed boundary method. The simulation has been carried out under the constant bulk mean velocity and bulk mean temperature at the bulk Reynolds number Re_b = 3550 and the Prandtl number Pr = 1. There are two cases in this study. The one is a flow with a chamber outside of the porous wall, and the other one has no chamber. By arranging the chamber, the heat transfer is significantly enhanced compared to the no-chamber case. In this case, we have found that large-scale spanwise roll structures, leading to the dissimilar heat transfer enhancement, emerge due to the generation of blowing and suction on the porous wall.