Non-Darcy axisymmetric free convection on permeable horizontal surfaces in a saturated porous medium

A unified study is made of non-Darcy axisymmetric free convection on horizontal surfaces in a fluid saturated porous medium. The surfaces, across which is a lateral mass flux, are assumed to be permeable. Similarity solutions are obtained when the surface temperature varies as the square root of the radial distance or when the surface heat flux is constant. The effect of the non-Darcy parameter and lateral mass flux on the rate of heat transfer and energy convected through the boundary layer are discussed. The rate of heat transfer is shown to be less in non-Darcy convection than in Darcy convection.