Entropy generation due to natural convection cooling of a nanofluid

In the present work, entropy generation due to natural convection of a nanofluid that consists of water and Cu in a cavity with a protruded heat source has been studied. To investigate both the First and the Second Law of Thermodynamics for this considered problem the numerical scheme carried out based on finite volume method with the SIMPLE algorithm for pressure-velocity coupling. In this study, the effect of Rayleigh number, solid concentration and heat source location on entropy generation have been revealed. Consequently the optimum case has been selected since the thermal system could have the least entropy generation and the best heat transfer rate. The results have shown the maximum value of Nusselt number and minimum entropy generation are obtained when heat source mountains in the bottom horizontal wall. (C) 2011 Elsevier Ltd. All rights reserved.