Radiation effects on free convection over a vertical flat plate embedded in a porous medium with high porosity

Free convection of an optically thin dense fluid along an isothermal vertic al surface embedded in a porous medium with high porosity has been studied. With appropriate transformations the boundary layer equations are reduced to local nonsimilarity equations. Numerical solutions of these equations ar e obtained by using the Keller box scheme as well as the local nonsimilarit y method with second order truncation. The nonsimilar equations governing t he flow are simulated by the above methods for fluid of Prandtl number equa l to 5.4, Also, effects of the pertinent parameters, R-d, the radiation-con duction parameter and Delta, the surface heating parameter and also the mod ified Grashof number, Gr*, on the local skin friction and the local rate of heat transfer are shown graphically. (C) 2001 Editions scientifiques et me dicales Elsevier SAS.