Abstract
Natural convection fluid flow and heat transfer in a shallow rectangular cavity containing two stratified fluid layers, one atop the other, is investigated numerically. The thermal conditions art heating and cooling by a constant heat flux through the vertical sides, keeping top and bottom walls insulated. The governing equations are solved using finite difference methods with a matching of the temperature, heat transfer rate, velocity, and shear stress across the interface between two fluid layers. The surface tension dependence on temperature is also taken into consideration. It is demonstrated that five different patterns of convection can be observed in the present system. Velocity and temperature distributions, stream function, and local and average Nusselt numbers are presented over a wide range of governing parameters. The numerical solution is compared with a theoretical study reported in the literature.