Effects of Variable Viscosity on Heat and Mass Transfer over an Exponentially Porous Stretching Surface

Abstract

Abstract
This study was conducted to investigate the effects of variable viscosity in boundary layer flow on heat and mass transfer of
incompressible viscous fluid over a porous stretching surface in the presence of thermal radiation. The equations governing
fluid flow, heat and mass transfer were simplified using similarity variables. Appropriate parameters were introduced to
transform the governing equations. The transformation was used to reduce the governing system of Partial differential
equations to a set of nonlinear Ordinary Differential Equations, which were then solved numerically using the fourth-order
Runge-Kutta method with shooting techniques. The numerical computations for variable fluid parameters controlling fluid
flow, heat and mass transfer as well as the effect of varied parameters on velocity, temperature and concentration were
presented in tabular and graphical forms. The results showed that an increase in radiation produced a marginal rise on the
velocity, temperature and concentration profiles. Skin friction, Nusselt and Sherwood number increased/decreased with
varied parameters. It was further observed that increased variation of magnetic parameter ratio led to a corresponding
increase in Skin friction, Nusselt number and Sherwood numbers. The results revealed that increase in Sc. parameter led to
increase in Skin friction, Nusselt and Sherwood numbers.