Analysis of effective thermal conductivity for non-uniform porous media

In this paper, heat conduction in rigid polyurethane foam, one kind of typical non-uniform porous media, is analyzed and simulated, in which finite volume method and interface harmonic average thermal conductivity are adopted. The calculated results show that inner structure acts as the main influencing factor. The influencing degree is consequent on the thermal conductivities of both matrix and pore. The calculated effective thermal conductivity agrees well with the experimental data. The conclusions of this work can be extended to more complicated situations of non-uniform porous media and can be used for engineering calculation.