Effects of Brownian motion and Thermophoresis on MHD Mixed Convection Stagnation-point Flow of a Nanofluid Toward a Stretching Vertical Sheet in Porous Medium

Abstract

This article deals with the study of the two-dimensional mixed convection magnetohydrodynamic (MHD) boundary layer of stagnation-point flow over a stretching vertical plate in porous medium filled with a nanofluid. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis in the presence of thermal radiation. The skin-friction coefficient, Nusselt number and local Sherwood number as well as the velocity, temperature and concentration profiles for some values of the governing parameters were presented graphically and discussed in detail for both the cases of assisting and opposing flows. It was observed that, the magnitude of the reduced Nusselt number decreases with the increases in the Brownian motion and thermophoresis effects for both cases of buoyant assisting and opposing flows. In addition to, the local Sherwood number increases by increasing the Brownian motion in both cases of buoyant assisting and opposing flows. A similar effect on the local Sherwood number was observed when thermophoresis effects decreases.

Keywords

• MHD mixed convection
• Stagnation-point flow
• Stretching vertical plate
• Nanofluid
• Brownian motion