考虑迟滞非线性的高超声速飞行器颤振分析

Flutter analysis on hypersonic aircraft considering hysteresis nonlinearity

为给飞行器颤振控制及结构设计等提供支持,利用适合复杂结构建模的动态子结构方法中的自由界面模态综合法,考虑飞行器在超声速飞行状态下高超声速流和飞行器自身结构的特点,将整个飞行器分成多个子结构;考虑飞行器机身与机翼之间相互连接构件的实际工作状况和制造工艺情况,带有间隙非线性与立方非线性相互作用所产生的迟滞非线性特性,以及阻尼因子对非线性的影响,用有限元计算软件计算各子结构的动力学特性参数和气动力分布情况,建立飞行器整机的振动微分方程以分析颤振特性.对得到的飞行器在所设工况下的振动和颤振特性及颤振临界状态进行分析,实现全机气动弹性问题的仿真计算.分析结果表明,该方法拓展高超声速飞行器颤振的计算,可为动态子结构方法应用于颤振研究提供参考.

To provide support for aircraft flutter control and structure design and so on, the free interface modal synthesis method of dynamic substructure method, which fits for complex structure modeling, is used to divide an aircraft into several substructures considering hypersonic flow and aircraft structure characteristics under supersonic flying condition; considering the actual working condition and manufacture technology of the connecting components between aircraft body and wings, the hysteresis nonlinearity effect generated by the interaction of occasional nonlinear effect and cubic nonlinear effect, and the effect of damping factor on the nonlinearity, a finite element software is used to calculate the parameters of dynamic characteristics and aerodynamic distribution of each substructures, the entire aircraft vibration differential equations are established, and the flutter characteristics are analyzed. The vibration, flutter characteristics and flutter critical situation are analyzed for the designed aircraft under the assumed condition. So the simulation and calculation on the aeroelastic problem of the entire aircraft is implemented. The analysis result indicates that the method can extend the calculation of hypersonic aircraft flutter issue and provide references for the application of dynamic substructure method on flutter study.