Radiation Heat Transfer in Ceramic Re-Entry Heat Shields.

The material parameters commonly used, those of emissivity and the radiative component of thermal conductivity, are examined to determine their validity in characterizing the heat transfer processes in a radiative re-entry heat shield. This is done by comparing calculations of radiative heat fluxes and temperature distributions of two models. The first one uses the standard heat conduction equation employing the above parameters, while the second is based on more exact radiative transfer theory that uses the radiation parameters of the absorption and scattering coefficients. Results of these calculations indicate that for typical aerodynamic heat fluxes calculated temperature distributions for the two models varied significantly, particularly near the surface. Author