Investigation of different nanofluids effect on entropy generation on natural convection in a porous cavity

In the present study, entropy generation in the porous square cavity filled with nanofluid in natural convection using lattice Boltzmann method considering wide range parameters of natural convection and effect of different porosities in constant Darcy numbers with various volume fractions of nanofluid has been investigated. Nanofluid comprises of water as base fluid and solid Al2O3, TiO2 and CuO as nanoparticles. Effect of these nanofluid in entropy generation, average Nusselt number and heatlines are studied while horizontal walls are adiabatic, temperature of the Left wall changes according to sinusoidal behavior and right wall is maintained at constant temperature According to prediction, maximum total entropy is generated in the vicinity of high temperature walls in the present study. Also the results indicate that average Nusselt number and entropy generation are the increasing function of porosity but the entropy generation is a decreasing function of volume fractions of nanofluid. (C) 2016 Elsevier Masson SAS. All rights reserved.