AEROELASTIC ANALYSIS CONSIDERING STRUCTURAL UNCERTAINTY

Abstract

Uncertainties in aero elastic analysis are investigated. In aero elastic analysis, we usually find divergence speed or flutter speed by using deterministic equations of motion for elastic wings of aircraft. If any parameter in these equations is sensitive to the critical speed, we should treat it carefully since inaccuracy is inevitable in the production process. Tragic failure may occur if the margin is small. Therefore, it is important to know in the analysis the effects of uncertainties of the critical values when they play a critical role in the design. The sensitivity of parameters in aero elastic analysis is not simple even in linear analysis. It is not always possible to have an analytic form of the sensitivity of uncertainty. In order to evaluate the structural sensitivity of aero elastic phenomena, we have to resort to numerical calculations with uncertain parameters having some random deviations, i.e. the so‐called Monte Carlo simulation. In the present study, the divergence speed and flutter speed of a typical wing section with structural uncertainties are discussed, and some results of calculations with scattering parameters in Gaussian distribution will be presented.