Thermal dispersion-radiation effects on non-Darcy natural convection in a fluid saturated porous medium

The effects of thermal dispersion and thermal radiation on the non-Darcy na tural convection over a vertical flat plate in a fluid saturated porous med ium are studied. Forchheimer extension is considered in the flow equations. The coefficient of thermal diffusivity has been assumed to be the sum of m olecular diffusivity and the dispersion thermal diffusivity due to mechanic al dispersion. Rosseland approximation is used to describe the radiative he at flux in the energy equation. Similarity solution for the transformed gov erning equations is obtained. Numerical results for the details of the velo city and temperature profiles which are shown on graphs have been presented . The combined effect of thermal dispersion and thermal radiation, for the two cases Darcy and non-Darcy porous medium, on the heat transfer rate whic h are entered in tables is discussed.