纳米酚醛气凝胶材料高温热物性参数辨识方法

临近空间高超声速飞行器大面积区域可能广泛采用纳米酚醛气凝胶(IPC)材料，获取高超声速气动加热作用下IPC材料的高温热物性参数，对于高超声速飞行器热防护系统的精细化设计具有重要的意义。考虑烧蚀效应的材料高温热物性参数辨识方法研究，基于Ablation Workshop烧蚀热响应标准算例对高温热物性参数辨识方法进行验证，计算结果表明：热物性参数辨识分析方法计算精度较高；通过带分层温度/烧蚀传感器的IPC材料电弧风洞试验，得到典型来流状态下不同厚度IPC材料内部的温度分布及热解厚度分布数据，通过辨识获得高温烧蚀条件下IPC材料热导率随温度的变化关系，IPC材料原始层热导率在温度低于800 K时随温度缓慢上升（热导率维持在0.1 W/(m·K)以下），之后材料热解使得热导率发生突变，碳化层热导率在温度高于800 K时随着温度的上升急剧增大，到1 300 K左右时上升到0.17 W/(m·K)。

High temperature thermal conductivity estimation method of inorganic-organic hybrid phenolic composites

The inorganic-organic hybrid phenolic composite (IPC) tends to be widely used for the thermal protection of near-space hypersonic vehicles. The thermal conductivity estimation of IPCs plays an important role in the fine design of thermal protection system. A thermal conductivity identification method considering ablation effect is proposed and verified based on the benchmark of Ablation Workshop. The results show the computation precision of the proposed method. Through the arc wind tunnel test of IPCs with stratified temperature and ablation sensors, the temperature and pyrolysis thickness distribution data of IPCs with different thicknesses are obtained, and the relationship between the thermal conductivity and temperature of IPCs is achieved. Before 800 K, the thermal conductivity of the original layer of the IPC increases slowly with temperature, remaining below 0.1 W/(m·K). After 800 K, however, changes occur abruptly, and the thermal conductivity of the carbonization layer increases sharply with the increase of temperature, reaching 0.17 W/(m·K) at 1300 K.