Abstract:
A suitable laboratory test procedure is developed where a small fragment of the relatively thick multilayer heat shield is exposed to the extreme heat flux of up to several kW/cm$^2$ in order to evaluate its performance. A nearly one-dimensional test condition has been achieved, where thermal behavior of a small fragment of a large shield became representative for the large heat-shield panel. A cylindrical test sample made of carbon-carbon composite has been surrounded by high-temperature thermal isolation made of zirconia concrete. The high heat flux has been provided by a power CW-laser. The conditions of one-dimensional axial heat flux through the cylindrical fragment of the heat shield are confirmed by the mathematical modeling of the experiment using experimentally measured temperature excursions along the sample axis.