Aeroelastic stability analysis using stochastic structural modifications

Abstract

An experimental-based approach to flutter speed uncertainty quantification in aeroelastic systems is developed. The proposed technique considers uncertainty from a post-manufacture perspective. Variability due to manufacturing tolerances, damage and degradation is formulated as a stochastic structural modification to a single set of measured receptance data. The Sherman-Morrison formula is exploited so that the probability of flutter is evaluated either from parameter bounds or by using a first-order reliability method. The advantage of the formulation is that there is no requirement to model either the structure or aerodynamics, thereby avoiding model-form and parameter uncertainties. Numerical examples are provided, which demonstrate the efficiency of the method when compared to conventional Monte-Carlo simulation (MCS). The method is also demonstrated in experimental examples and it is shown to be eminently practical since the data required for MCS is generally not available in industrial practice.