中文摘要：

提出了轻质热防护系统外面板使用多层结构的概念，设计了2种热防护材料组合构成的3种铺层方案．通过模拟飞行器再入大气层时受到的机械和热载荷条件，数值计算得到了层间剪切力、底部温度和Y方向位移．计算结果发现，层间剪切力发生在边缘部位且呈反对称分布；选用高热导率和高热容材料能够减少材料内的温度梯度，进而有效地降低结构的热应力和热变形；在均匀温度场情况下，两种材料的热膨胀系数之差越小，则层间剪切力越小．该研究表明不同的材料组合和铺层次序的多层结构，可以满足不同设计要求，具有优化设计潜力．

英文摘要：

A design concept of using multflayer structure for the top face-sheet of a lightweight thermal protection system was proposed. To obtain the different structural performances, three schemes were considered according to the different stacking orders of two kinds of insulation materials. With the mechanical and thermal loads during aircraft reentry considered, internal thermal stress of the multilayer structure was simulated. Details of shear stresses, temperature of the bottom surface and y-direction displacement were obtained. The results show that the shear stresses occur at the edge area, and the distributions are anti-symmetrical along the mid- line. The usage of the materials with high thermal conductivity and heat capacity can reduce the temperature gradient and then the thermal stresses and deformation. With the uniform tempera- ture field, the difference of the thermal expansion coefficients of two materials is positively re- lated with the shear stress between the two materials. It is suggested that, there is a great po- tential of optimization design for the multilayer structure through different combinations of ma- terials in different stacking orders.