UNSTEADY AERODYNAMICS MODELLING AND ITS APPLICATION IN AEROELASTIC STABILITY ANALYSIS

摘要

An identification technique is used to constructreduced-order models (ROMs) for theincompressible flow past a circular cylinder atlow Reynolds numbers. The proposed method iscapable of constructing simple models for boththe stable and unstable flows at the vicinity ofcritical Reynolds number. Linear ROMs arethen validated in the time domain by comparingtheir harmonic forcing responses to that of fullsystem in direct numerical simulations. Finally,the validity of linear ROMs is most clearlyshown by using them for stability analysis of anelastically-mounted cylinder. The instabilityboundaries predicted by the linear dynamicsmodel compare reasonably well to that of directCFD/CSD simulations, while the computationalcost can be reduced by nearly 2 orders ofmagnitude. Moreover, this kind of linear ROMscan also be utilized to feedback controllerdesign and active flow control in furtherresearch.