TRANSIENT LOW PRANDTL NUMBER FLUID CONVECTION IN A LID-DRIVEN CAVITY

Abstract

Transient convective motion and heat transfer in a square cavity driven by combined temperature gradient and imposed lid shear are analyzed. The cavity is filled with a low Prandtl fluid, and the vertical walls are maintained at different but constant temperatures. The horizontal connecting walls are adiabatic. The upper wall is moving and either aids or opposes the buoyancy-driven motion. A control volume method is employed to compute the flow and temperature fields. Numerical results are reported for Pr = 0·005, Gr = 1 × I0⁷, and a range of Reynolds numbers for both aiding and opposing flow situations. The evolution of unsteady flow in a cavity is discussed. For GrIRe² ≥ 1 the effect of inertia is insignificant. For GrIRe² ≤ 1 the inertia stabilizes the flow, regardless of the direction of the applied shear force.