Technological watch

The thermo-physical parameters of the pyrolysis layer in charring material play a fundamental role in the design of the thermal protection system (TPS) in hypersonic vehicles, but there is still a lack of measuring methods for the pyrolysis layer including pyrolysis gases, carbon residue and resin. The measuring method for the thermal conductivity of the pyrolysis layer is presented by means of iteration inversion of temperature at measuring points, and experimental equipment is designed and manufactured. Furthermore, the thermal conductivity of the pyrolysis layer under different pressures is obtained by this method. The results reveal that its thermal conductivity is a nonlinear function of temperature; meanwhile, the pressure has a major effect on the thermal conductivity. This study can figure out the test problem of the thermal conductivity of the pyrolysis layer, which is helpful to the optimization of TPS.