This study aims at characterising the role played by uncertainties in the very particular aeroelastic problem which is being investigated within the special session "Progress of the 3rd Aeroelastic Prediction Workshop Large Deflection Group". The subject of the analysis is a Wind Tunnel model, the "Pazy wing", developed by Prof Raveh of Technion characterised by "large displacements". In this study, the aeroelastic analysis is carried out on the basis of an analytical model - with CFD-tuned aerodynamics and a structural model fine-tuned to match experimental stiffness and eigenfrequencies. Uncertainties are propagated to the quantities of interest (e.g. flutter speed) via Non-Intrusive Polynomial Chaos Expansion. The motivation for this study is to provide some guidance to other potential participants, who are currently approaching the problem with higher fidelity methods / tools, mostly based on a coupled FEM / CFD time - accurate calculations. The analytical model is for the time being used in its linear implementation and only with a zero angle-of-attack. However, its results in terms of complex eigenvalues and flutter speed are consistent with those obtained by Prof Raveh with more conventional tools. According to the preliminary findings, the flutter speed 95% confidence interval is several m/s broad, a surprisingly high value, in the same order of magnitude of the differences expected between lower and higher fidelity modelling approaches.
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