Abstract
Radiation effects in the two-dimensional stagnation-point flow of viscous nanofluid due to solar energy are investigated. Heat transfer subject to thermal radiation, Joule heating, viscous dissipation and convective boundary conditions is considered. A different application of Rosseland approximation for thermal radiation is introduced in this study. The governing equations are simplified through the boundary layer assumptions and then transformed into non-dimensional forms by appropriate transformations. The resulting differential systems are solved numerically through fourth-fifth order Runge-Kutta method (RK45) using a shooting technique. The influences of different parameters are explained through graphs for velocity, temperature and concentration and numerical values of local Nusselt and Sherwood numbers. A comparative analysis of the solutions is performed through previous studies in some limiting cases. Both the temperature and wall temperature gradient are increasing functions of the radiation parameter. The excessive movement of nanoparticles in the base fluids results in the deeper absorption of solar radiations in the liquids. (C) 2013 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.