Computation of conjugate heat transfer in the turbulent mixed convection regime in a vertical channel with multiple heat sources

摘要

This paper presents the results of a comprehensive numerical study to analyze conjugate, turbulent mixed convection heat transfer from a vertical channel with four heat sources, uniformly flush-mounted to one of the channel walls. The results are presented to study the effect of various parameters like thermal conductivity of wall material (k_s), thermal conductivity of flush-mounted discrete heat source (k_c), Reynolds number of fluid flow (Re_s), modified Richardson number (Ri~+) and aspect ratio (AR) of the channel. The standard k-ε turbulence model, modified by including buoyancy effects with physical boundary conditions, i.e. without wall functions, has been used for the analysis. Semi-staggered, non-uniform grids are used to discretise the two dimensional governing equations, using finite volume method. A correlation, encompassing a wide range of parameters, is developed for the non-dimensional maximum temperature (T~*) using the asymptotic computational fluid dynamics (ACFD) technique.