Passive control of nonlinear aeroelasticity in hypersonic 3-D wing with a nonlinear energy sink

Nonlinear aeroelastic behaviors of a three-dimensional (3-D) trapezoidal wing coupled with a nonlinear energy sink (NES) in hypersonic flow are investigated. A NES is used to suppress the wing flutter and mitigate the aeroelastic responses. Based on the von Karman large deformation theory and the third-order piston theory, the nonlinear aeroelastic governing equations of trapezoidal wing-like plate with a NES are built by using the Rayleigh-Ritz approach combined with the affine transformation. The energy transfer mechanism of NES is analyzed by an energy-based approach. The comparisons of bifurcation diagrams between the trapezoidal wing-like plates without and with NES show that the NES has a stabilizing effect on the system in the pre-flutter regime and enhances the flutter boundary. The NES can absorb and dissipate the energy provided by the airflow though resonance capture, and the nonlinear responses of the wing-like plate can be suppressed completely in the post-flutter regime. However, the passive control performance of the NES degrades for a higher dynamic pressure, and the NES is even no longer capable of mitigating aeroelastic responses especially for chaotic motions. Furthermore, a parametric design is conducted to evaluate the influences of the NES's parameters on its performance. The results reveal that the NES-based structure design has good effectiveness for delaying the onset of wing flutter and reducing vibration amplitude.