Numerical Investigation of Mixed Convection Heat Transfer from Block Mounted on a Cavity

Abstract

This work aims to numerically investigate the mixed convective flow over a three-dimensional cavity that lies under the horizontal channel with a vertical heat source projecting from the bottom of the cavity. This investigation is progressed by establishing the boundary conditions of the walls of vertical heat source as isothermal, while backward and the forward facing steps as isothermal at ambient temperatures and the rest of the walls are adiabatic. The flow is laminar and incompressible in the cubic geometry. A numerical simulation is undertaken to investigate the flow structure, heat transfer characteristics and the complex interaction between the induced stream flow at ambient temperature and buoyancy-induced flow from the walls of the heated source. The numerical simulations are performed using commercial CFD codes. The numerical codes are validated with previously published benchmark results. The study is performed for three different Reynolds numbers (100, 500 and 1,000) and subsequently for three different Richardson numbers (0.1, 1 and 10) for each Reynolds number. The height of the vertical heat source is kept constant for all the above-mentioned cases. A special case is undertaken to study the flow characteristics and heat transfer for increased depth of the cavity.