Features of Natural Convective Air Flows Inside Vertical Parallel-Plate Channels Subject to Step Heat Fluxes: Insulated Upstream and Heated Downstream

This paper addresses the impact of adding insulated extensions at the entrance of a parallel-plate channel in which the plates receive a uniform heat flux and a natural convection air flow is responsible for the cooling. The full elliptic conservation equations are solved numerically in a composite I-type computational domain. It was found that the wall temperatures increase when the channel extensions are appended at the inlet. The pertinent results are reported in terms of maximum wall temperatures, induced mass flow rates, as well as velocity, pressure and temperature profiles of the fluid.