A study of pore scale flow and conjugate heat transfer characteristics in real and Kelvin anisotropic foams

Abstract

Porous foam is a promising material in the field of science and engineering owing to its potential to offer heat transfer enhancement. In this work, an ideal Kelvin structure with considering anisotropy is constructed based on the characteristic parameters extracted from a real foam, and the flow and heat transfer characteristics in real and Kelvin foams is numerically investigated and compared by an in-house MRT-TLBM solver accelerated by a GPU. Results demonstrate that when the flow is along the elongation direction of the structure, the permeability is larger and Nusselt number is lower than those in the other directions for both real and Kelvin foams. Compared to the real foam, the Kelvin foam is more prone to inducing turbulence. For the overall performance of flow and heat transfer, the real foam behaves better at small Reynolds number (Rec <750), while Kelvin foam does when Rec exceeds 750 due to the different dominant mechanisms of heat transfer. In particular, the comprehensive factor (θ) of Kelvin foam is 12.8 % larger than that of the real foam at Rec=2000.