Thermal radiation effects on magnetohydrodynamic flow past a semi-infinite vertical plate in the presence of mass diffusion

Abstract

Magnetohydrodynamic (MHD) mixed free–forced heat and mass convective steady incompressible laminar boundary layer flow of a gray optically thick electrically conducting viscous fluid past a semi-infinite vertical plate for high temperature and concentration differences is studied. A uniform magnetic field is applied perpendicular to the plate. The density of the fluid is assumed to reduce exponentially with temperature and concentration. The usual Boussinesq approximation is neglected because of the high temperature and concentration differences between the plate and the ambient fluid. The Rosseland approximation is used to describe the radiative heat flux in the energy equation. The boundary layer equations governing the flow are reduced to ordinary differential equations, which are numerically solved by applying an efficient technique. The effects of the density–temperature parameter n, the density–concentration parameter m, the local magnetic parameter Mx, and the radiation parameter R are examined on the velocity, temperature, and con- centration distributions as well as the coefficients of skin-friction, heat flux, and mass flux.PACS No.: 44.27+g