适 用 于 复 杂 流 动 的 热 气 动 弹 性 降 阶 建 模 方 法

For aerothermoelastic problems dominated by complex flow on hypersonic vehicles，an unsteady aerody⁃ namic Reduced-Order Modeling （ROM） method suitable for time-varying thermal modal shapes was developed，based on which a fluid-thermal-structural coupling framework using spatial and temporal data exchanging strategy was finally constructed. Above framework was applied to predict time-varying flutter boundary of an air intake compression surface installed on hypersonic vehicle forebody in actual aerodynamic heating process. As is shown in the results，modal frequencies and modal shapes varied greatly with time when the compression surface was exposed in extremely uneven heat flow，and proposed ROM method is suitable for such variation of modal shapes，which means repetitive CFD calculation of unsteady aerodynamic force can be saved. By adopting proposed ROM，generalized aerodynamic force can be calculated with high confidence and time consumption is several orders of magnitude lower than traditional methods. Aerothermoelastic analysis of compression surface revealed that flutter dynamic pressure was reduced to 0. 64% of the value at initial time after reaching thermal equilibrium，which significantly narrows flight envelop of hyper⁃ sonic vehicle. The proposed method effectively alleviates the contradiction between efficiency and accuracy of aero⁃ thermoelastic analysis，and improves the engineering feasibility of aerothermoelastic analysis.