Influence of non-Darcy and MHD on free convection of non-Newtonian fluids over a vertical permeable plate in a porous medium with soret/dufour effects and thermal radiation

Abstract

This study investigated the effects of non-Darcy (Forchheimer equation) and magnetohydrodynamic (MHD) forces on free convection of non-Newtonian fluids over a vertical permeable plate in a porous medium with Soret/Dufour effects and thermal radiation. The vertical plate surface has a uniform wall temperature and uniform wall concentration (UWT/UWC). Non-similar solutions for the transformed governing equations are obtained by Keller box method. Comparisons showed excellent agreement with numerical data reported in previous works. Numerical data entered in tables or plotted in figures for the dimensionless temperature profile, the dimensionless concentration profile, the local Nusselt number and the local Sherwood number are presented for the main parameters: the non-Darcy parameter ND, the magnetic field parameter M, the power-law index of the non-Newtonian fluid n, the blowing/suction parameter ξ and the thermal radiation parameter Rd. The numerical results show that increasing the non-Darcy parameter ND or the magnetic field parameter M tends to decrease both the local Nusselt number and the local Sherwood number. Additionally, increasing the thermal radiation parameter Rd increases both the local Nusselt number and the local Sherwood number. Generally, for the case of suction, both the local Nusselt number and the local Sherwood number increase. The opposite trend occurs in the case of blowing fluid.