[01] Samir Kumar Nandy, Department of Mathematics, A.K.P.C Mahavidyalaya, Bengai, Hooghly, India. [02] Rajib Kumar Mandal, Department of Physics, A.K.P.C Mahavidyalaya, Bengai, Hooghly, India.

This paper analyzes the combined effects of magnetic field, Brownian motion, thermophoresis and thermal radiation on stagnation–point flow and heat transfer due to nanofluid towards a nonlinearly stretching/shrinking sheet. A variable magnetic field is applied normal to the sheet. Using a similarity transformation, the governing mathematical equations are transformed into coupled nonlinear ordinary differential equations which are then solved numerically using fourth order Runga–Kutta method with shooting technique. Different from a nonlinearly stretching sheet, it is found that the solutions for a nonlinearly shrinking sheet are non-unique. The numerical results pertaining to the present study indicate that the magnetic field parameter enhances the existence range of solution domain. The influences of various relevant parameters on flow, temperature and concentration as well as skin friction coefficient, local Nusselt number and local Sherwood number are investigated. A comparison with the previous study available in the literature is done and we found an excellent agreement with them.

Stagnation-Point Flow, Heat Transfer, Nanofluid, Magnetic Field, Thermal Radiation

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