Vibration localization due to flutter instability in a bladed rotor

The current push toward lightweight structuresin aerospace and aeronautical engineering is leadingto slender design airfoils, which are more likelyto undergo large deformation, hence experiencing geometricalnonlinearities. The problem of vibration localizationin a rotor constituted by N coupled airfoils withplunge and pitch degrees of freedom subjected to flutterinstability is considered. For a single airfoil, it is年代hown that depending on the system parameters, multiple年代tatic and dynamic equilibria coexist which maybe a fixed point, a limit cycle, or irregular motion.By elastically coupling N airfoils, a simplified rotormodel is obtained. The nonlinear dynamical responseof the rotor is studied via time integration with particularattention to the emergence of localized vibrating年代olutions, which have been classified introducinga localization coefficient. Finally, the concept of basin年代tability is exploited to ascertain the likelihood of the年代ystem to converge to a certain localized state as a functionof the airstream velocity. We found that homogeneous and slightly localized states are more likely toappear with respect to strongly localized states.

Just published in Nonlinear Dynamics

https://link.springer.com/article/10.1007/s11071-020-06171-8

https://www.researchgate.net/profile/Antonio_Papangelo