Effect of Knudsen Number on Effective Thermal Conductivity of Two Phase Materials

Abstract

In this article, collocated parameter models are developed to estimate thermal conductivity of two-phase materials by including the effects of pressure and temperature dependent parameter, Knudsen number. The algebraic expressions are derived for both touching and non-touching two-dimensional and three-dimensional spatially periodic geometries based on unit cell approach. The models are used to predict thermal conductivity of various two-phase materials with conductivity ratio between 1 to 1000 at various temperatures and pressures. The models are validated with published experimental data for various temperatures and pressures and it shows good agreement with experimental data with ±7.53%, ±8.66% for high pressures and ±14.22%, ±9.75% at low pressures for materials with high conductivity ratio(100< <1000) and low thermal conductivity ratio (<100) respectively