Thermophoresis Effect On Unsteady Free Convection Heat And Mass Transfer In A Walters-B Fluid Past A Semi Infinite Plate

The effect of thermophoresis particle deposition on unsteady free convective, heat and mass transfer in a viscoelastic fluid along a semiinfinite vertical plate is investigated. The Walters-B liquid model is employed to simulate medical creams and other rheological liquids encountered in biotechnology and chemical engineering. The dimensionless unsteady, coupled and non-linear partial differential conservation equations for the boundary layer regime are solved by an efficient, accurate and unconditionally stable finite difference scheme of the Crank-Nicolson type. The behavior of velocity, temperature and concentration within the boundary layer has been studied for variations in the Prandtl number (Pr), viscoelasticity parameter (), Schmidt number (Sc), buoyancy ration parameter (N) and thermophoretic parameter ( ). The local skinfriction, Nusselt number and Sherwood number are also presented and analyzed graphically. It is observed that, an increase in the thermophoretic parameter ( ) decelerates the velocity as well as concentration andaccelerates temperature. In addition, the effect of the thermophoresis is also discussed for the case of Newtonian fluid.