THERMO-DIFFUSION AND DIFFUSION-THERMO EFFECTS ON FREE CONVECTION FLOW PAST A HORIZONTAL CIRCULAR CYLINDER IN A NON-DARCY POROUS MEDIUM

摘要

An analysis is presented for the steady free convection heat and mass transfer past a horizontal circular cylinder plate in a non-Darcy porous medium with Soret (thermo-diffusion) and Dufour (diffusion-thermo) effects included. The non-Darcy effects are simulated via a second-order Forchheimer drag force term in the momentum boundary-layer equation. A parametric study illustrating the influence of Darcy parameter Da, Forchheimer parameter A, Grashof number Gr, Schmidt number Sc, Soret number Sr, Dufour number Du, transpiration parameter f_w, on the fluid velocity, temperature, and concentration profiles, as well as local skin friction, Nusselt, and Sherwood numbers, is conducted. Increasing Darcy number accelerates the flow due to a corresponding rise in permeability of the regime and concomitant decrease in Darcian impedance. Applications of the model arise in metallurgical materials processing, chemical engineering, flow control, etc.