Heat transfer of non-Darcy MHD flow of nano fluid over a stretching/shrinking surface in a thermally stratified medium with second order slip model

The present investigation is mainly focused on the problem of heat transfer of an incompressible magnetohydrodynamic non-Darcy flow of a water based nano fluid with different metallic and non metallic nanoparticles, over a stretching/shrinking sheet embedded in a thermally stratified porous medium, in the presence of thermal radiation and internal heat generation/absorption, with a second order slip flow model. To analyze the problem elaborately, numerical simulations are carried out. Moreover, an analytical treatment is performed for a special case. The results for nano fluid velocity, temperature, skin friction coefficient and reduced Nusselt number are discussed. It is found that a unique solution exists in the stretching sheet and dual solutions are obtained for the shrinking sheet, which are classified as upper and lower branch solutions. Some of the notable results of the nanoparticle volume fraction, non-Darcy, slip and stratification parameters are brought out, which may be applicable for future research work. To validate the present code, results are compared with benchmark solutions and observed an excellent agreement. (C) 2015 Sharif University of Technology. All rights reserved.