Numerical Study of Turbulent Natural Convection in an Enclosure with Conjugate Heat Transfer

Abstract

The standard high Reynolds number two equation k −ε model is used to numerically study the turbulent natural convection in an enclosure with conjugate heat transfer. The right vertical side wall and the top wall are considered to have some finite thickness. The effect of wall thickness on the fluid flow and the heat transfer characterstics for Rayleigh number ranging from 109 to 1011 is considered here. The wall thickness is varied as 0.1, 0.075, 0.05 times the enclosure dimension. The fluid flow and thermal characteristics are presented in the form of streamlines, velocity vectors, turbulent kinetic energy, and isothermal contour plots. The variation of local heat flux and the local Nusselt number along the vertical side wall is also presented. The finite volume method based SIMPLE algorithm is utilised for understanding the nature of flow. The convective flux is discretised using the power law scheme while the diffusive term is discretised using central difference scheme.