Thermal diffusion and diffusion thermo effects on unsteady MHD free convection flow over a stretching surface considering Joule heating and viscous dissipation with thermal stratification, chemical reaction and hall current

Abstract

The present investigation is concerned with the effects of thermal-diffusion and diffusion-thermo on an unsteady MHD free convection boundary layer flow with heat and mass transfer of an electrically conducting fluid over a stretching sheet in the presence of strong magnetic field with Hall current, thermal stratification, chemical reaction, heat generation, thermal radiation, Joule heating and viscous dissipation. The transformed nonlinear boundary layer equations are numerically solved by applying Keller-box method. The influence of various embedded flow parameters on the local skin friction, the local Nusselt number and the local Sherwood number has been carefully analyzed through graphs. It is found that the shear stress and the rate of mass transfer increase with an increasing of current density Jh while the reverse trend is observed on the rate of heat transfer. It is also found that the shear stress and the rate of heat transfer increase with an increasing of Sr, whereas the reverse trend is observed on the rate of mass transfer. Further, the shear stress and the rate of mass transfer increase with an increasing of Du while the reverse trend is seen on the rate of heat transfer. The numerical results are compared and found to be in good agreement with previously published results under special cases.