On the effect of model uncertainty on the Hopf bifurcation of aeroelastic systems Articles uri icon

publication date

  • January 2021

start page

  • 1453

end page

  • 1473

issue

  • 2

volume

  • 103

International Standard Serial Number (ISSN)

  • 0924-090X

abstract

  • This paper investigates the effect of model uncertainty on the nonlinear dynamics of a generic aeroelastic system. Among the most dangerous phenomena to which these systems are prone, Limit Cycle Oscillations are periodic isolated responses triggered by the nonlinear interactions among elastic deformations, inertial forces, and aerodynamic actions. In a dynamical systems setting, these responses typically emanate from Hopf bifurcation points, and thus a recently proposed framework, which address the problem of robustness from a nonlinear dynamics viewpoint, is employed. Briefly, the notion of robust bifurcation margin extends the concept of ¿ analysis technique from the robust control theory. The main contribution of this article is a systematic investigation of the numerous scenarios arising in the study of nonlinear flutter when uncertainties in the model are accounted for in the analyses. The advantages of adopting this framework include the possibility to: quantify relevant information for the determination of the nonlinear stability envelope; gain a more in-depth understanding of the physical mechanisms triggering subcritical and supercritical Hopf bifurcations; and reveal properties of the nominal system by identifying isolated branches not straightforward to detect with conventional numerical approaches. © 2021, The Author(s).

keywords

  • aeroelasticity bifurcations robustness aeroelasticity dynamical systems dynamics robust control uncertainty analysis hopf bifurcation point in-depth understanding limit cycle oscillation (lco) model uncertainties non-linear stabilities nonlinear interactions numerical approaches supercritical hopf bifurcation hopf bifurcation