Viscous Dissipation Effects on Heat Transfer for Nanofluid Flow Over a Backward-Facing Step Through Porous Medium Using Lattice Boltzmann Method

A numerical study of viscous dissipation effects on incompressible forced convection flow of nanofluids over a two dimensional horizontal backward facing-step (BFS) placed in a porous channel is carried out in a laminar flow regime. In the flow modeling, the Brinkman-Forchheimer extended Darcy model (DBLF) is incorporated in the momentum equation and the local thermal equilibrium (LTE) assumption is assumed for study. Therefore, in the energy equation, the viscous dissipation effects are included. The obtained governing differential equations for the consideraded physical problem are solved by the Lattice Boltzmann method (LBM). Special attention is given throughout this paperunderstanding the effect of dynamic and thermal parameters such as volume fraction (phi), type of nanoparticles, Darcy number (Da), Eckert number (E-c), Reynolds number (Re), heat capacity ratio (R-c) and heat conductivity ratio on flow and heat transfer (R-k).