高超声速气动热弹性分析降阶研究

Reduced-order modeling research for hypersonic aerothermoelastic analysis

高超声速气动热弹性分析涉及流场、结构场和热力场间的相互耦合,计算复杂且耗时长。根据分层求解策略提出了一种基于降阶模型的高超声速气动热弹性分析框架。分别采用系统辨识法和本征正交分解法对高超声速气动力和气动热建立降阶模型,并与模态叠加法耦合实现热配平状态下气动热弹性问题的快速计算。以典型高超声速三维机翼为例,预测热结构的颤振动压,并与全阶流⁃固⁃热耦合计算结果对比吻合较好。所提出的气动热弹性分析框架提高了计算效率,而且精度高,可应用于工程分析中。

Aerothermoelastic analysis of hypersonic vehicle involves the coupling of fluid field,structural field,and thermal field,and as a result is complicated and time-consuming.In this paper,a hypersonic aerothermoelastic analysis method based on reduced-order models is developed according to the hierarchical solution strategy.The system identification method and the proper orthogo-nal decomposition method are used to establish the reduced-order models of the hypersonic aerodynamic force and aerodynamic heating,respectively.Then,these reduced-order models are combined with the modal superposition method to realize the rapid cal-culation of aerothermoelastic problems under the static aerothermoelastic trim.Taking a typical hypersonic three-dimensional wing as an example,the flutter speed of the thermal structure is predicted,and is in good agreement with the calculation of the full-order fluid-solid-thermal coupling model.The aerothermoelastic analysis framework proposed in this paper is accurate and greatly im-proves the calculation efficiency,which can be applied to the engineering analysis.