运载火箭尾段防热/承载一体化热防护系统设计及性能分析

先进热防护技术是可重复使用运载火箭研制的关键技术之一,具有高结构效率的防热/承载一体化热防护系统是运载火箭极具潜力的备选热防护方案。本文系统地总结了可重复使用运载火箭尾舱段防热和承载两方面的设计要求,设计了一种全复合材料防隔热/承载一体化热防护系统。开展了运载火箭尾段一体化热防护系统设计,进行了代表性单胞结构的高温环境地面试验,揭示了复合材料一体化热防护系统的防隔热机理。同时施加力学和热流载荷,利用有限元方法对运载火箭尾段进行了热力耦合分析,获得了尾段结构的温度场、应变场和应力场。结果表明:在典型载荷工况下一体化热防护系统内壁温度保持在89.2℃以下,内部最大应力不超过9.53 MPa,安全系数达到1.89。

Design and Property Analysis of Integrated Thermal Protection System for Tail Cabin of Launch Vehicle

The advanced thermal protection technology is one of the key technologies for the research and development of reusable launch vehicles. The integrated thermal protection system (ITPS) with high structural efficiency is an alternative thermal protection scheme of great potential for launch vehicles. The design requirements of both thermal protection and load bearing capacities for tail cabins of reusable launch vehicles are systematically summarized, and an all-composite ITPS is designed. The application research of the ITPS in the tail cabin of a launch vehicle is carried out, and high temperature thermal exposure tests for the representative unit cell structure are performed. The thermal insulated mechanisms of the all-composite ITPS are revealed. In addition, the coupled thermal-mechanical analysis is conducted by using the finite element method and applying both thermal and mechanical loads. The temperature, strain, and stress distributions of the tail cabin are obtained. The results show that the internal surface temperature of the tail cabin is kept below 89.2 ºC, the maximum stress does not exceed 9.53 MPa, and the safety factor of the ITPS is 1.89.