基于CFD技术,运用系统辨识方法,建立了基于模态坐标的跨音速气动力降阶模型(ROM)。耦合气动状态方程、结构状态方程和伺服状态方程,建立了一个适合跨音速伺服气动弹性分析的数学模型。算例首先通过对比基于ROM技术的分析结果和直接仿真结果,以证明该模型的正确性和精度。在保证精度的同时,其计算效率比直接耦合CFD技术的仿真方法高1个~2个数量级。算例还研究了传感器安放位置和结构陷幅滤波器对该导弹伺服气动弹性特性的影响,结果显示结构陷幅滤波器的引入可以显著地降低开环气动弹性系统和控制系统的耦合。
Based on computational fluid dynamics and system identification technique, the reduced order model (ROM) for transonic unsteady aerodynamics stemmed from the structural mode coordinates is firstly established. Coupled aerodynamic state equations, structural state equations and servo state equations, a model for transonic aeroservoelastic analysis are developed. The results computed by analytical method based on ROM are compared with those by CFD direct simulation method, which are used to demonstrate its correctness and precision. The computational efficiency is improved by 1-2 orders while retaining the accuracy of the CFD based direct simulation method. Then the examples show the effect of the sensor's locations on the aeroservoelastic system. Finally, the study indicates that the addition of structural filter can reduce the effect of the active control system on the open loop aeroelastic system.