Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations

X. Q. Wang, Z. Zhang, Z. Zhou, Marc Mignolet, P. C. Chen

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Several recent studies of the occurrence of post-flutter limit cycle oscillations (LCO) of the F-16 have provided good support to the long-standing hypothesis that this phenomenon involves a nonlinear structural damping. The proposed mechanism for the appearance of nonlinearity in the damping are the nonlinear geometric effects that arise when the deformations become large enough to exceed the linear regime. In these investigations, a finite-element based reduced order modeling (ROM) framework with nonlinearity in damping has been developed. In this approach, the aircraft material is assumed to be viscoelastic with a dissipation tensor proportional to the elasticity tensor. The coefficient of proportionality, denoted as γ, represents the single tunable parameter of the model. With an appropriate calibration of this parameter, a good match between flight test LCO amplitudes and those predicted by the model has been obtained on average for each configuration tested. Fluctuations between predictions and flight test data have however been observed that suggest the presence of uncertainties, both aleatoric (e.g., variability from aircraft to aircraft) but also likely epistemic (i.e., unmodeled dynamics) ones. Accordingly, the focus of the present investigation is on developing a stochastic model of the F-16 aeroelastic response with uncertainty on the nonlinear damping properties and assessing the resulting band of uncertainty for some configurations analyzed in prior efforts.

Original languageEnglish (US)
Title of host publicationAIAA Scitech 2019 Forum
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
ISBN (Print)9781624105784
DOIs
StatePublished - Jan 1 2019
EventAIAA Scitech Forum, 2019 - San Diego, United States
Duration: Jan 7 2019Jan 11 2019

Publication series

NameAIAA Scitech 2019 Forum

Conference

ConferenceAIAA Scitech Forum, 2019
CountryUnited States
CitySan Diego
Period1/7/191/11/19

Fingerprint

Damping
Tensors
Aircraft materials
Aircraft
Stochastic models
Elasticity
Calibration
Uncertainty

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Wang, X. Q., Zhang, Z., Zhou, Z., Mignolet, M., & Chen, P. C. (2019). Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations. In AIAA Scitech 2019 Forum (AIAA Scitech 2019 Forum). American Institute of Aeronautics and Astronautics Inc, AIAA. https://doi.org/10.2514/6.2019-1752

Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations. / Wang, X. Q.; Zhang, Z.; Zhou, Z.; Mignolet, Marc; Chen, P. C.

AIAA Scitech 2019 Forum. American Institute of Aeronautics and Astronautics Inc, AIAA, 2019. (AIAA Scitech 2019 Forum).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Wang, XQ, Zhang, Z, Zhou, Z, Mignolet, M & Chen, PC 2019, Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations. in AIAA Scitech 2019 Forum. AIAA Scitech 2019 Forum, American Institute of Aeronautics and Astronautics Inc, AIAA, AIAA Scitech Forum, 2019, San Diego, United States, 1/7/19. https://doi.org/10.2514/6.2019-1752
Wang XQ, Zhang Z, Zhou Z, Mignolet M, Chen PC. Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations. In AIAA Scitech 2019 Forum. American Institute of Aeronautics and Astronautics Inc, AIAA. 2019. (AIAA Scitech 2019 Forum). https://doi.org/10.2514/6.2019-1752
Wang, X. Q. ; Zhang, Z. ; Zhou, Z. ; Mignolet, Marc ; Chen, P. C. / Effects of nonlinear structural damping uncertainty on f-16 limit cycle oscillations. AIAA Scitech 2019 Forum. American Institute of Aeronautics and Astronautics Inc, AIAA, 2019. (AIAA Scitech 2019 Forum).
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