Conductive and Radiative Heat Transfer in Foam Materials at High Temperatures

Abstract

At high temperatures, heat transfer in foams occurs by conductions through solid matrix and air as well as by thermal radiation propagating the structure. Starting from the analysis of different foam morphological structures, the body-centered cubic cell model is applied to predict the conductive and radiative properties. Both the open foams and the closed foams are analyzed. Temperature-dependency of the material properties is also taken into consideration. The Rosseland approximation is used to predict the radiativie conductivity. Effects of temperature, cell diameter and porosity on the equivalent thermal conductivity are discussed. It is found that both the temperature and the structure parameters have strong influences on the equivalent thermal conductivity.