Keywords: 3D cavity, entropy generation, natural convection, double diffusive

Abstract:In this paper we study numerically the 3D double-diffusive natural convection in a cubic cavity. The main purpose of this paper is to study the effect of the modification of the boundary condition of the upper and down sides of a cubical cavity, on the flow and heat transfer in the one side and on the entropy generated on the other side. The flow is considered laminar and caused by the interaction of thermal energy and the chemical species diffusions. The governing equations of the problem, concentration, energy and momentum, are formulated using vector potential-vorticity formalism in its three-dimensional form, then solved by the finite volumes method. The Rayleigh number is fixed at Ra=105 and the effects of the buoyancy ratio is studied for opposed temperature and concentration gradients. The particular interest is focalized on the three-dimensional aspects and entropy generation.