Tolerance indicating models of non-thermal and thermal damages for a heat transport system

For reusable high-speed vehicles, the damage accumulation in heat transfer paths during multitudes of missions leads to resistance augment, performance undermining, and even failures of heat transport (HT) systems. The quantitative characterization of tolerance for various damages becomes crucial to a reliable HT system. In this work, a stochastic model of size and volume fraction is used to describe the non-thermal damage which is caused by various non-thermal loads like mechanical vibration, impact, corrosion, etc., and a probability model considering probability gradient and local, reference, limit, and constraint temperatures is developed to characterize the thermal damage which is generated with the temperature increasing. A dendritic HT system is obtained by topologic optimization with the objective of the lowest geometric average temperature, and the heat transfer with multiple distributions of non-thermal and thermal damages is analyzed. The effects of size and volume fraction for non-thermal damage and that of constraint temperature and probability gradient for thermal damage on the HT performance are clarified. Two damage tolerance indicating models considering HT performance are then proposed by polynomial fittings and validated by extended numerical data.