Non-orthogonal stagnation point flow of a nano non-Newtonian fluid towards a stretching surface with heat transfer

This article investigates the theoretical study of steady stagnation point flow with heat transfer of a second grade nano fluid towards a stretching surface. It is assumed that the fluid impinges on the wall obliquely. The model used for the nano fluid incorporates the effects of Brownian motion and thermophoresis. The governing equations of second grade nano fluid are presented. The governing nonlinear partial differential equations are converted into nonlinear ordinary differential equations by using similar and non similar variables. The resulting ordinary differential equations are successfully solved analytically with the help of homotopy analysis method (HAM). Graphically results are shown for non-dimensional velocities, temperature and nanoparticle concentration. Numerical values of skin friction coefficients, diffusion mass flux and heat flux are computed. It is shown that a boundary layer is formed when the stretching velocity of the surface is less than the inviscid free-stream velocity and velocity at a point increases with the increase in the elasticity of the fluid. Comparison with previously published work is performed and excellent agreement is observed for the limited case of existing literature. (C) 2012 Elsevier Ltd. All rights reserved.