Natural convection in a square cavity partially filled with porous medium and nanofluid using Buongiorno's model

Abstract

Natural convection is investigated in a square cavity divided in three layers, nanofluid at the middle and the upper and lower parts for porous layer. The cavity is heated from the left and cold from the right at constant temperature Th and Tc respectively. The side walls are well insulated. The Buongiorno’s model was used to evaluate the distribution of nanoparticles and takes account the Brownian and thermophoresis motion. The governing equations are solved by the Galerkin finite element method. The governing parameters are Rayleigh (103≤ Ra ≤ 106), porous layer thickness (0.3 ≤ Lp ≤ 0.05).The result shows that increasing buoyancy forces reinforce circulation flow in the nanofluid layer than the porous layer, the decrease effect of porous layer thickness improve considerably the convective heat transfer. The heat and mass transfer are enhanced.