Analysis of combined conductive-radiative heat transfer in a twodimensional rectangular enclosure with a gray medium

A first-principle approach is used to analyze combined conductive/radiative heat transfer in a high porosity silica insulation materials (LI900) currently used by the Space Shuttle. Using the measured value of the refractive index (n, κ), solutions to the radiative transfer equation for fibrous insulation with a random packing geometry is used to generate macroscopic average radiative properties such as extinction coefficient, scattering albedo and phase function. Based on a non-gray application of the zonal method, transient thermal response of the insulation tile subjected to an external radiant flux is generated and compared with experimental data. The agreement is excellent. The computation is both efficient an