A comparative study of uncertainty quantification methods in gust response analysis of a Lift-Plus-Cruise eVTOL aircraft wing

TL;DR

This paper compares various uncertainty quantification methods to assess their effectiveness in predicting the structural response of an eVTOL aircraft wing under stochastic gust conditions, highlighting variability and sensitivity in the responses.

Contribution

It provides a comprehensive comparison of non-intrusive UQ methods applied to a complex aeroelastic model for eVTOL wings, revealing their relative performance and limitations.

Findings

Significant variability in structural responses due to uncertainties.

Performance of UQ methods varies with risk measures and quantities of interest.

System sensitivity to gust and flight condition uncertainties is high.

Abstract

Wind gusts, being inherently stochastic, can significantly influence the safety and performance of aircraft. This study investigates a three-dimensional uncertainty quantification (UQ) problem to explore how uncertainties in gust and flight conditions affect the structural response of a Lift-Plus-Cruise eVTOL aircraft wing. The analysis employs an unsteady aeroelastic model with a one-way coupling between a panel method aerodynamic solver and a shell analysis structural solver to predict the wing's response under varying conditions. Additionally, this paper presents a comparative evaluation of commonly used non-intrusive UQ methods, including non-intrusive polynomial chaos, kriging, Monte Carlo, univariate dimension reduction, and gradient-enhanced univariate dimension reduction. These methods are assessed based on their effectiveness in estimating various risk measures-mean, standard deviation, and 95th percentile-of critical structural response outputs such as maximum tip displacement and average strain energy. The numerical results reveal significant variability in the structural response outputs, even under relatively small ranges of uncertain inputs. This highlights the sensitivity of the system to uncertainties in gust and flight conditions. Furthermore, the performance of the implemented UQ methods varies significantly depending on the specific risk measures and the quantity of interest being analyzed.