A Mixed Convection Boundary Layer Flow over a Vertical Wall in a Porous Medium, with Exponentially Varying Fluid Viscosity

Eunice Mureithi

Department of Mathematics, University of Dar es Salaam, Dar es Salaam, Tanzania.

DOI: 10.4236/jamp.2014.28087                

Abstract

This study investigates a mixed convection boundary layer flow over a vertical wall embedded in a highly porous medium. The fluid viscosity is assumed to decrease exponentially with temperature. The boundary layer equations are transformed into a non-similar form using an appropriate non-similar variable ξ and a pseudo-similar variable η. The non-similar equations are solved using an efficient local non-similarity method. The effect of viscosity variation parameter on the heat transfer, skin friction and the velocity and temperature distribution within the boundary layer is investigated. The viscosity variation parameter, the viscous dissipation parameter and non-simi-larity variable are shown to have a significant effect on velocity and thermal boundary layer and also on the skin friction coefficient and heat transfer at the wall.

Keywords

Porous Medium, Non-Darcy, Mixed Convection Boundary Layer, Temperature Dependent Viscosity

Conflicts of Interest

The authors declare no conflicts of interest.

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