Natural Convection of a 2D Cavity with Bottom Heating: Discrete Versus Continuous Heating Distributions

Abstract

We present a study on natural convection in square cavities with both continuous and discrete heating distributions by using lattice Boltzmann method. For all cases studied, the lower surface is heated, the right one is considered as a partially cooling boundary, and the rest region of the walls are defined as adiabatic. The comparison on flow and heat transfer between two different heating distributions is presented. The effects on the unit heating source length ([[EQUATION]]), the spacing (d) between two separate heating sources, and the total number of the heating sources (n) on convection are revealed. The novelty resides in the fact that we compare the flow performance differences between employing continuously and discretely distributed heating strategies, the effect of which is discussed. Besides, the thermal boundary conditions are different from the ones used other studies [1-19], being for the present study, the bottom wall partially or entirely heated, the right sidewall partially cooled and the rest of the walls are adiabatic. Moreover, the discrete distribution is employed as equi-spaced in the present study. The combined effect of three parameters [[EQUATION]], d and n on heat transfer is analyzed. For practical purpose, our conclusions lead to a more appropriate strategy for indoor heating, specifically when the budget of total heating length ([[EQUATION]]) is limited, or the cost-saving is considered.

Keywords: Natural convection, steady states, discrete heating distribution, heat transfer, indoor floor heating