A novel TE-material based thermal protection structure and its performance evaluation for hypersonic flight vehicles

The traditional thermal protection system (TPS) of hypersonic flight vehicles is usually designed for thermal protection purpose only with low efficiency. In this paper, a thermoelectric material based multifunctional TPS structure concept is proposed and the evaluation approach of its mechanical-thermoelectric performance is developed based on a specific vehicle and a typical trajectory. The thermoelectric module in the structure can convert a certain amount of aerodynamic heat into electricity supply. The module consists of n-type Sr_0.9La_0.1TiO₃ compound which is fabricated based on the solid state reaction method, and the widely used p-type Ca₃Co₄O₉. For a specific hypersonic flight vehicle with a typical trajectory curve, the aerodynamic heat is calculated by an engineering-based algorithm, the unsteady mechanical-thermoelectric characteristics of the structure is then analyzed based on a unit cell model and the thermoelectric conversion efficiency is finally evaluated. The results indicate that the multifunctional TPS structure has significant application potentials on the hypersonic flight vehicles.