Thermal Conductivities of Porous Solids

In heat-transfer experiments with porous solids, the void fractions of the solids were varied systematically. A brief review is given of some of the literature relevant to the subject. The thermal conductivities of porous solids were evaluated. In the evaluation, radiative heat transfer in spherical voids was investigated. It is shown that various parameters have an effect on the heat transfer of porous material. An equation is proposed to describe this heat transfer. Heat-transfer experiments were carried out with porous solids. Within the experimental conditions used in the present study, the experimental values are in good agreement with the values secured from the literature. (16 refs.)