Robust Flutter Analysis Considering Mode Shape Variations

摘要

Any aircraft analysis model is subject to simplifications to some extent, leading to uncertainties in the nominal model. Therefore, analysis based on the numerical model generally yields errors in the aerodynamic loads, structural behavior, and critical speeds. Robust flutter analysis usually aims at computing a worst-case flutter speed considering these uncertainties, but can also be used to consider larger variations, such as fuel burn. In recent years, so-called μ analysis [1] from the control community has been applied to perform robust flutter analysis [2,3]. Most recently, Borglund [4,5] combined classical frequency-domain aeroelasticity with μ analysis to formulate the μ-k method, being closely related to the p-k and g methods [6,7]. In particular, a simple and efficient μ-k algorithm that takes advantage of data from a p-k or g method analysis is described in [8].