Unsteady heat and mass transfer mechanisms in MHD Carreau nanofluid flow

In this article, we study the unsteady heat and mass transfer mechanisms in a magnetohydrodynamic (MHD) Carreau nanofluid flow induced by a permeable stretching surface. The Buongiorno's model is used to incorporate the effects of Brownian motion and thermophoresis. The local similarity transformations are employed to alter the leading partial differential equations to a set of ordinary differential equations. The resulting non-linear ordinary differential equations are solved numerically by an effective numerical approach namely bvp4c function in MATLAB to explore the effects of physical parameters. The velocity, temperature and nanoparticle concentration profiles have been calculated for both shear thinning and shear thickening fluids. A very good agreement is noticed between the present results and previous published works in some limiting cases. It is important to mention here that the dimensionless temperature and nanoparticle concentration are higher in the presence of magnetic field. The analysis further reveals that the local Nusselt number and local Sherwood number are decreasing functions of the thermophoresis parameter. (C) 2016 Published by Elsevier B.V.