The problem of thermal diffusion and magnetic field effects on combined freeforced convection and mass transfer flow past a vertical porous flat plate, in the presence of heat generation is studied numerically. The governing momentum, energy and concentration equations are converted into a system of nonlinear ordinary differential equations by means of similarity transformations. The resulting system of coupled nonlinear ordinary differential equations is solved numerically by using the Shooting method. Numerical results are presented for velocity, temperature and concentration profiles within the boundary layer for different parameters of the problem including suction parameter, heat generation parameter, Soret number, Dufour number, magnetic parameter, etc. In addition, the effects of the pertinent parameters on the skin friction and the rates of heat and mass transfer are discussed numerically and illustrated graphically.
IntroductionThe analyses of the flow behavior of exotic lubricants, the flow of colloidal suspensions or polymeric fluids, liquid crystals, additive suspensions, animal blood and turbulent shear flows are generally very complicated. The study of such mixed convection flow finds application in several industrial and technical processes, e.g., the cooling of nuclear reactors during emergency shutdown, solar central receivers exposed to winds, electronic devices cooled by fans and heat exchangers placed in low-velocity environments. The simplest physical model of flow is the two-dimensional laminar mixed convection flow along a vertical flat plate and extensive studies have been conducted on this type of flow [1][2][3][4]. Applications of this model can be found in the areas of reactor safety, combustion flames and solar collectors, as well as building energy conservation [5]. This model has also been used by many investigators to analyze the combined free-forced convective boundary layer flow, for micropolar fluids, and for the flow through porous media [6][7][8][9][10][11][12]. However, in the above studies mass diffusion due to a temperature gradient, called thermal diffusion has not been taken into account. Jha and Singh [13] and Kafoussias [14] have noted the importance of the effects of this thermal diffusion. Recently, Alam and Sattar [15] included the thermal diffusion effect on MHD free convection and mass transfer flow. Alam et al. [16] studied the above mentioned effect on unsteady MHD free convection and mass transfer flow past an impulsively started vertical porous plate. Alam et al.[17] also studied the above mentioned thermal diffusion effects as well as heat generation effects on combined free-forced convection and mass transfer flow past a semi-infinite vertical porous flat plate embedded in a porous medium in the absence of a magnetic field, i.e., M = 0 and Dufour parameter, D f = 0 1) . Hence, the objective of the present paper is to study the above mentioned thermal diffusion and magnetic field effects on combined free-forced convection and mass transfer flow past a vert...
