Radiative heat transfer of a two-fluid flow in a vertical porous stratum

Abstract

The effect of thermal radiation on mixed convection flow of two immiscible fluids in a vertical porous stratum is considered in the presence of a heat source or sink. The flow model is based on the Darcy-Lapwood-Brinkman equation. The general governing momentum and energy equations for the immiscible fluids are coupled and nonlinear and cannot be solved in closed form. However, approximate analytical solutions are obtained for small values of? = Pr Ec (the product of the Prandtl and Eckert numbers) using the regular perturbation method, while numerical solutions are found for large values of ?. A representation of the results is presented graphically to illustrate the influence of the physical parameters on the solutions. It is found that both the velocity and temperature fields can be controlled effectively by altering the values of the viscosity ratio, width ratio, and heat generation or absorption coefficient.©2008 Begell House, Inc.