Influence of thermophoretic particle deposition on MHD free convection flow of non-Newtonian fluids from a vertical plate embedded in porous media considering Soret and Dufour effects

摘要

This study numerically investigates the combined heat and mass transfer of an electrically conducting, non-Newtonian power-law fluid in MHD free convection adjacent to a vertical plate within a porous medium in the presence of the thermophoresis particle deposition effect. The governing boundary layer equations along with the boundary conditions have been first transformed by a similarity transformation into a set of coupled, non-linear ordinary differential equations, and the resulting similarity equations are then solved by the local adaptive differential quadrature method (La-DQM). Some important parameters have been discussed in this study, which include the magnetic parameter Ma, the buoyancy ratio N, the Dufour number D_f and the Soret number S_r. Effects of these major parameters on the fluid, heat and mass transfer processes are carried out. The results indicate that the wall friction decreases as the magnetic parameter increases or the buoyancy ratio decreases. Increasing the Soret number or decreasing the Dufour number tends to decrease the temperature distribution inside the boundary, but tends to increase the concentration variation. In addition, the thermophoretic deposition velocity decreases as the magnetic parameter or the Dufour number increases, while it increases as the buoyancy ratio or the Soret number increases.