关键词: 模型确认, 不确定性建模, 气动弹性系统, 参数化, μ分析方法, 鲁棒颤振分析

Abstract: The problems of uncertainty modeling and model validation of a wing aeroelastic system are investigated. The parametric uncertainties in structure are considered and both the parametric form and the unmodeled dynamic form which are used to represent the uncertainty in unsteady aerodynamic forces are discussed. The linear fractional transformation (LFT) representation of an uncertain aeroelastic system is formulated to perform model validation and robust flutter analysis. Easily computable tests in the frequencydomain for the existence of a model validating set are given, and then a parameterization of the model validating sets is implemented and the smallest uncertainty set is determined based on optimization algorithms. The influence is considered of exogenous disturbances and noise of unknown but energy bounded sources that actually exist in practice, and this could reduce the conservatism of the results. Finally, for an uncertain aeroelastic system with the obtained uncertainty magnitudes, a robust flutter analysis based on the structured singular value theory is performed to predict the robust stability boundary. Numerical results of the simulation demonstrate the validity of the developed method.

Key words: model validation, uncertainty modeling, aeroelastic systems, parameterization, μanalysis method, robust flutter analysis