Flutter Prediction for Flight/Wind-Tunnel Flutter Test Under Atmospheric Turbulence Excitation

• Published in: Journal of aircraft 2013-11, Vol.50 (6), p.1696-1709
• Main Authors: Zeng, Jie, Kukreja, Sunil L
• Format: Article
• Language: English
• Subjects: Aerodynamics; Aeroelasticity; Aeronautics; Aerospace engineering; Air transportation and traffic; Aircraft; Applied sciences; Atmospheric turbulence; Damping; Decomposition; Exact sciences and technology; Excitation; Flexible structures; Flutter analysis; Frequency response functions; Fundamental areas of phenomenology (including applications); Ground, air and sea transportation, marine construction; Methods; Parameter estimation; Perturbation; Physics; Power; Solid mechanics; Structural and continuum mechanics; Trends; Turbulence; Vibration; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Wind tunnel testing; Wind tunnels
• ISSN: 0021-8669; 1533-3868
• DOI: 10.2514/1.C031710

In this paper, a flutter-boundary prediction technique for an aeroelastic/aeroservoelastic structure is introduced. This approach uses time-series flight/wind-tunnel flutter test data to compute an accurate estimate of the flutter speed. The flutter-boundary prediction tool discussed in this paper can be categorized into three steps.1)Signal preprocessing techniques are introduced to estimate the frequency-response function if the external excitation signal is measurable or compute the autopower spectrum when only responses from sensors can be measured due to a strong turbulence perturbation during flight flutter test.2)A frequency-domain system-identification methodology combined with a stabilization diagram is implemented to extract the elastic modes of a flexible structure. Accuracy of modes estimated in the second step directly affects the robustness of flutter prediction.3)The flutter-prediction analysis can therefore be performed with the implementation of an appropriate flutter-prediction tool such as the Zimmerman–Weissenburger flutter margin and/or damping trends extrapolation methods.Application of the proposed flutter-boundary prediction method to the Aeroelastic Test Wing I and SuperSonic SemiSpan Transport model demonstrates that it is an efficient tool for flutter-boundary prediction of aeroelastic/aeroservoelastic structures.