Analyzing and predicting the nonlinear aeroelastic response

老化飞机或携带重型外挂的作战飞机可能在其飞行包线内出现非线性气动弹性现象，如极限环振荡（LCO）。一般来说，LCO对飞机性能有负面影响，但由于非线性，有限幅度的LCO比破坏性颤振振荡的发作更好。因此，在飞行器设计和主动自适应控制研究中，检测非线性的存在是非常重要的。此外，找出非线性的特定类型也很重要。该项目的主要目标是开发检测与气动弹性系统相关的非线性的方法，并预测变化飞行条件下的气动弹性响应。所提出的方法结合了数学分析和统计方法。这些方法仅使用一组瞬态数据，就能识别非线性并确定气动弹性系统的渐近状态。与气动弹性响应类似的振荡可以在许多其他非线性动力系统的输出中找到。因此，本项目不仅在非线性气动弹性研究方面具有很强的潜力，而且在分析非线性性质以及预测金融或生物医学复杂数据方面也具有很强的潜力。

Aging aircraft or operational aircraft carrying heavy externals may exhibit nonlinear aeroelastic phenomena, such as limit cycle oscillations (LCO), within their flight envelope. Generally the LCO has a negative effect on the aircraft performance, but limited amplitude LCOs due to non-linearities, are a better alternative than the onset of destructive flutter oscillations. Thus, for the flight vehicle design, and in the study of active and adaptive control, it is important to detect the presence of the non-linearities. Moreover, finding the particular type of the non-linearities is also important. The main objective of this project is to develop methods for detecting the nonlinearities associated with an aeroelastic system, and to predict the aeroelastic response for changing flight conditions. The proposed methodology incorporates mathematical analysis and statistical methods. Using only a set of transient data, these methods are capable of identifying nonlinearities and determining the asymptotic state of the aeroelastic system. Oscillations similar with the aeroelastic response can be found as the output of many other nonlinear dynamical systems. Thus, the present project has a strong potential not only in the study of nonlinear aeroelasticity, but also in the analysis of the nature of nonlinearities and in the prediction of financial or biomedical complex data.