气动热问题是制约高超声速飞行器发展的关键问题之一,其产生的热流对结构固有特性具有显著的影响.热模态分析是研究热载荷对结构固有特性影响的一个重要方法,其分析结果对防热结构的选材与设计具有重要的参考价值.针对高超声速飞行器进气道前缘结构开展了热载荷分析与应用研究,计算了结构在冷壁热流及通过流-固耦合法解算的热壁热流两种载荷条件下的温度场及前三阶模态的振动幅度与固有频率的变化情况.结果表明:采用流-固耦合算法解算的热载荷适用于持续气动加热环境下的结构热分析及热模态分析.耦合计算600 s后受热结构逐渐趋于热平衡,此时最高温度达到1200 K左右,前三阶模态的最大相对振动幅度分别增长了24.4％、5.6％和36.7％,固有频率分别下降了14.1％、8.8％和9.9％.%Aeroheating effect is one of the key problems that obstacle the hypersonic aircraft development; because its heat flux has very apparent effect on the structure natural characteristics. Thermal modal analysis is an important method to calculate the influence of thermal load on the natural characteristics of structure, and the analysis results have a great value for thermal protection structure' s selection and design. A thermal load analysis and application research is carried out on the hypersonic vehicle leading edge, to analyze the temperature field and the former three modal' s vibration amplitudes and natural frequencies under two kinds of thermal loading conditions: cold wall heat flux; and hot wall heat flux, calculated by fluid-structure coupling algorithm. The results show that the hot wall heat flux is suitable for structure thermal and thermal modal analysis in the continuous aerodynamic heating environment. It also shows that after calculating 600 seconds by fluid-structure coupling algorithm, the heated structure gradually reaches thermal equilibrium. At the moment, the structure' s maximum temperature reaches 1 200 K, the former three modal' s relative vibration amplitudes increased by 24. 4% , 5. 6% and 36. 7% , and the frequencies reduced by 14. 1% , 8. 8% and 9. 9% , respectively.
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