Lattice Boltzmann simulation of conjugate heat transfer in a rectangular channel with wall-mounted obstacles

Abstract

Conjugate heat transfer in a rectangular channel with lower and upper wall-mounted obstacles is investigated using the Lattice Boltzmann Method (LBM). Laminar and incompressible flow of fluid circulating through the channel is assumed. The simulations are performed at Pr=0.72. Studies are carried out for flow, with Reynolds numbers ranging from 200 to 1000, thermal diffusivity ratios (10, 100 and 1000) and the distance between obstacles, which are prescribed as multiples of obstacle width. A uniform heat flux through the base of obstacles is assumed. Results show that LBM is suitable for the study of heat transfer in conjugate problems. Results indicate that increase of thermal diffusivity yields to the removal of a higher quantity of energy from obstacle faces. Results also show that reducing the distance between obstacles makes the flow deviate and accelerate in the vicinity of faces, and causes an increase in the rate of convective heat transfer from obstacles.