Abstrakt

Double Diffusive Mixed Convection at a Vertical Plate in the Presence of Magnetic Field

T. R. K. D. Vara Prasad, C. N. B. Rao and P. Hari Prasad

An isothermal permeable plate is assumed to be immersed vertically in a homogeneous viscous electrically conducting fluid containing a concentration species. The fluid is assumed to be moving with a constant velocity parallel to the plate. Assuming fluid viscosity to be a function of temperature and taking into consideration the effect of Ohmic heating, double diffusive magneto hydrodynamic (MHD) mixed convection flow and heat transfer at the vertical plate is studied numerically. Assuming the flow to be twodimensional and introducing a similarity variable, the governing equations of the problem are reduced to a set of non-linear ordinary differential equations. The equations subject to appropriate boundary conditions are solved by Nachtsheim-Swigert scheme together with a Shooting method. Both the cases of assisting and opposing buoyancies are considered. The effects of magnetic field, Ohmic heating and mass diffusion on different flow and heat transfer characteristics like skin friction, Nusselt number and Sherwood number are presented graphically and discussed. Skin friction, and Nusselt number are found to diminish and Sherwood number is found to increase with increasing values of the Schmidt number. In the assisting flow case the Skin friction, the Nusselt number as well as the Sherwood number increase while in opposing flow case, they diminish with different parameters