Abstract
Natural convection and viscous dissipation in a square porous enclosure using a thermal nonequilibrium model is studied numerically in the present article. The horizontal heating is considered, where the vertical walls heated isothermally at different temperatures, while the horizontal walls are kept adiabatic. The Darcy model is used in the mathematical formulation for the porous layer and finite difference method is applied to solve the dimensionless governing equations. It is found that the average Nusselt number of fluid increases slightly by increasing the inter-phase heat transfer coefficient and the average Nusselt number of solid increases sharply by increasing the inter-phase heat transfer coefficient for the all viscous dissipation parameter.