Thermophoresis in natural convection with variable properties

The present paper deals with thermophoresis in Pr natural convection with v ariable properties for a laminar flow over a cold vertical flat plate. Vari ation of properties like density, viscosity and thermal conductivity with t emperature is included in the formulation of the problem. Selection of comp onents for the property ratio is made by fitting the property values betwee n the desired temperature limits. For a selected fluid, Prandtl number vari ation with temperature is neglected and the Prandtl number corresponding to film temperature is used for the analysis. Solution is carried out by fini te difference method. Variation of wall concentration and wall flux along t he length of plate is studied. The effect of thermophoretic coefficient on wall concentration is also studied. Results are presented in the form of gr aphs. The result is compared with similarity solution by Runge-Kutta method and found to be accurate up to second decimal place.