Effects of magnetic field and suction/injection on convection heat transfer of non-Newtonian power-law fluids past a power-law stretched sheet with surface heat flux

The problem of magneto-hydrodynamic flow and heat transfer of an electrically conducting, non-Newtonian power-law fluid past a stretching sheet in the presence of a transverse magnetic field is analyzed. The surface of the stretching sheet is assumed to move with a power-law velocity and subject to uniform surface heat flux. The effects of suction or injection at the surface are considered. The resulting governing equations are transformed into nonlinear ordinary differential equations using appropriate transformations and then solved numerically based on central-difference approximations. The solution is found to be dependent on five governing parameters including the magnetic field parameter, the power. law fluid index, the sheet velocity exponent, the suction/blowing parameter, and the generalized Prandtl number. A systematical study is carried out to illustrate the effects of these major parameters on the sheet surface temperature, fluid temperature distributions in the boundary layer, the skin-friction coefficient and the local Nusselt number. (C) 2007 Elsevier Masson SAS. All rights reserved.