一种耐高温多层热防护结构的优化设计与性能

Optimization design and performance for multi-layer thermal protection structure at high temperature

为解决高速飞行器飞行过程中剧烈的气动加热问题,以“高温防热层+隔热缓冲层+核心隔热层”顺序设计的一体化多层热防护结构的传热过程为研究对象,建立了高温环境下热防护结构内部一维非稳态导热-辐射耦合传热模型,通过数值模拟计算得到了高温环境下热防护结构各层的温度分布。利用不同热防护材料的隔热性能差异,针对构建的热防护结构,提出了在满足一定约束条件下,以轻质多层热防护结构总质量和总厚度为目标函数的优化设计方案,得到了多层结构的最优几何参数,并通过实验考核了优化后热防护结构的防隔热性能。实验表明:该结构可耐受1 473 K的高温1 800 s而背温不超过370 K。

In consideration of the intense aerodynamic heating during the flight of the high speed vehicles,the heat transfer process of a multi-layer thermal protection structure designed in the sequence of“high-temperature thermal protection layer+thermal insulation buffer layer+core thermal insulation layer”was investigated,and a one-dimensional unsteady thermal conductivity-radiation coupled heat transfer model was established inside the thermal protection structure at high temperature environment.The temperature profile of each layer of the thermal protection structure at high-temperature environment was obtained by numerical simulation.Based on the difference of thermal insulation performance of various thermal protection materials,the optimal design scheme with the total mass and thickness of the lightweight multi-layer thermal protection structure as the objective function under certain constraints was proposed,the optimal geometric parameters of the multi-layer structure were obtained,and the anti-insulation performance of the optimized thermal protection structure was verified experimentally.The experimental results showed that the optimized thermal protection structure can withstand 1473 K for 1800 s while the back temperature was kept below 370 K.