• AN EXACT ANALYSIS ON FREE CONVECTIVE HEAT AND MASS TRANSFER FLOW OF MICROPOLAR FLUID IN POROUS MEDIA WITH FLUCTUATING WALL EMPERATURE

Abstract

In this paper an exact analysis is made to study the free convection mass transfer flow of a micropolar fluid past a vertical porous plate embedded in Darcian porous media. The semi- infinite plate is subjected to a constant suction velocity and the temperature near the plate is supposed to get jumped exponentially. The governing system of partial differential equations is first transformed into a system of ordinary differential equations using a set of asymptotic transformations. A parametric study demonstrating the physical influence of the micro-gyration parameter, vortex viscosity parameter, dimensionless material parameter and proportionality parameter on the fluid velocity, microrotation velocity, coefficients of shear stress and couple stresses as well as Nusselt and Sherwood numbers is performed. The closed form of solutions obtained is finally validated through graphs and in tabular form and the physical aspects of the problem are highlighted and discussed theoretically. The results show that, the linear velocity initially decreases thereafter increases due to increase in vortex viscosity parameter, while for an increase in vortex viscosity parameter, an increasing trend is observed for angular velocity. The increase in values of Prandtl number decreases the skin-friction co-efficient, while it is found increasing the couple stress coefficient. A comparative study reveals that, the coefficients of skin-friction as well the couple stresses are less in micropolar fluids than in conventional Newtonian fluids.