Thermal Protection Modular Design for High-Speed Aircraft Engines and Optimization Based on Design of Experiments

High-altitude and high-speed aircraft generate substantial aerodynamic heat during flight, creating a harsh thermal environment in the engine compartment that risks overheating and burnout of control components and fuel and lubricating oil accessories. Consequently, the thermal protection system (TPS) design for engine accessories has become one of the key technologies in hypersonic vehicle design. Based on certain TBCC, this paper uses a modular active-passive integrated TPS design and employs the quality management experimental design tool to optimize the design and decouple the method proposed on the modular design boundaries. This paper is the first to combine modular design with design of experiments (DOE) tools and apply them to the TPS of high-altitude and high-speed combined power accessories. The design scheme is optimized by identifying the main influencing factors. The optimized TPS scheme decreases the performance loss by 10% and increases cooling efficiency by 22–26%. The proposed engineering method shortens the development cycle significantly and improves efficiency by 78%. The modular design method for accessory TPS provided in this paper has good engineering applicability and can be widely used in the early stages of thermal protection scheme design, scheme optimization, scheme selection, and overall thermal management of hypersonic combined power systems.