The effects of variable viscosity and thermal conductivity on a three-dimensional free convection flow past a uniformly moving porous vertical plate with viscous dissipation and Joule heating in presence of a uniform transverse magnetic field have been studied numerically. The governing boundary layer equations with associated boundary conditions are converted to non-dimensional form. The Magnetic Reynolds number is considered small enough to neglect the induced hydro magnetic effect. The resulting non-linear partial differential equations are then solved using an iterative method for an implicit finite difference scheme. Effects of various flow governing parameters on the fluid velocity, temperature, concentration fields are presented graphically. Further, the coefficient of skin-friction, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form.

Effects of variable viscosity and thermal conductivity on MHD convective flow through a porous medium with chemical reaction have been investigated. The governing equations have been expressed in non dimensional form using non-dimensional variables, constants and similarity parameters; the resulting boundary value problem has been solved using shooting method. Velocity, temperature and the concentration profile are presented graphically. The coefficient of skin friction, rate of heat transfer in form of Nusselt number and the coefficient of mass transfer in terms of Sherwood number are also obtained and presented in tabular form. The effects of all the parameters are significant.