وحید فرهنگ مهر

In this paper, we have numerically examined the steady boundary layer of a viscous incompressible nanofluid and its heat and mass transfers above a horizontal flat sheet. The boundary conditions considered were a nonlinear magnetic field, a nonlinear velocity and convection. Such nonlinearity in hydrodynamic and heat transfer boundary conditions and also in the magnetic field has not been addressed with the great details in the literature. In this investigation, both the Brownian motion and thermophoretic diffusion have been considered. A similarity solution is achieved and the resulting ordinary differential equations (nonlinear) are worked numerically out. Upon validation, the following hydrodynamic and heat and mass transfers parameters were found: the reduced Sherwood and Nusselt numbers, the reduced skin friction coefficient, and the temperature and nanoparticle volume fraction profiles. All these parameters are found affected by the Lewis, Biot and Prandtl numbers, the stretching, thermophoretic diffusion, Brownian motion and magnetic parameters. The detailed trends observed in this paper are carefully analyzed to provide useful design suggestions.