UNSTEADY THERMAL FLUID TRANSPORT PHENOMENA IN SQUARE CAVITY UNDER REDUCED GRAVITY

Abstract

A numerical study is performed to investigate unsteady natural convection heat transfer and fluid flow in a cavity under reduced gravity. Consideration is given to the influence of Marangoni convection on the thermal and velocity fields in a two-dimensional square cell. Here, it consists of two opposing vertical side walls held at constant but different temperature with the horizontal lower wall insulated and the upper face treated as nondeformable adiabatic free surface. The fluid temperature gradient in the cavity in the absence of Marangoni force under the reduced gravity is substantially decreased near the hot and cold vertical walls and the dominant heat transfer mechanism switches from convection into conduction, as time progresses. On the contrary, the corresponding flow pattern and isotherms are similar to that under normal gravity condition, resulting in a slight deterioration of the heat transfer performance, if Marangoni force drives the flow in the cavity. Therefore the unsteady natural convection in the system considered is affected by the Marangoni force level.