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S. A. Amoo and A. S. Idowu

**keywords:** Exponentially stretching, MHD flow,porous media,thermal radiation

The study investigated thermal radiation effect on heat and mass transfer of magnetohydrodynamic (MHD) boundary layer fluid flow in a porous medium over an exponentially porous stretching sheet in the present of heat generation and chemical reaction. The governing boundary layer equations of the model were transformed to a system of ordinary coupled differential equations. The coupled system of equations were then solved numerically by a fourth order Runge-Kutta method along with shooting technique. A parametric study on the effect of variations in the fluid parameters on velocity, temperature and concentration were conducted and presented graphically. Also, the effect of radiation on heat and mass transfer as well as effects on skin friction, Nusselt and Sherwood number on some physical parameters were verified and discussed in detail. Thefindings included the numerical variation in Skin friction, Nusselt and Sherwood numbers at the surface with the introduced parameters i.e. Magnetic parameter, Darcy porosity parameter, permeability at the plate, Schmidt, Prandtl ratios, radiation and chemical reaction parameters which are of physical and engineering interest were presented. It can be seen from the results that an increase in the values of all listed parameters except thermal radiation decrease the flow boundary layer while increase in heat generation and thermal radiation increase the flow boundary layer. This study compares favourably with some existing studies in literature. Also, the effect of skin friction, Nusselt and Sherwood number on some physical parameters are verified and discussed in detail.

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