NUMERICAL-SIMULATION OF TRANSIENT NATURAL-CONVECTION FROM AN ISOTHERMAL CAVITY OPEN ON A SIDE

Numerical simulations are presented for buoyancy-induced flow and heat transfer in a square isothermal cavity open on a side. The vorticity- stream function formulation with improvised boundary conditions at the window of the cavity is employed. It is shown that flows at moderate to high Rayleigh numbers are periodic or unsteady. The interaction of the buoyant elements generated at the three sides and their entrainmen t characteristics are complex. The basic physical mechanisms underlyin g these complex flows are discussed in detail. Nusselt number data are provided for steady and unsteady flows.