Natural convection heat transfer from a vertical plate to high permeability porous media: an experiment and an approximate solution

Abstract

The heat transfer rate from an isothermal vertical plate placed next to saturated high permeability porous media is studied experimentally and analytically. The media used are polyurethane foams saturated with air. An integral method is applied in predicting the heat transfer rate by including the non-Darcy effects, which are expected to be significant for high permeabilities and high Rayleigh numbers. Good agreement is found between the experimental and predicted results except when the permeability is relatively low and the Peclet number becomes very small. Although some of the permeabilities encountered are large, for the experimental conditions considered in this study the Rayleigh numbers are not very high; therefore, the non-Darcy effects are not significant.