Panel flutter suppression via combined-nonlinear acoustic black hole

This study introduces an innovative combined-nonlinear acoustic black hole (CNABH) structure, integrating a nonlinear part and an acoustic black hole (ABH) part, for panel flutter suppression. To investigate its aeroelastic behavior, the coupled aeroelastic equations of panel with CNABH are derived by coupling the respective governing equations of the panel, ABH, and nonlinear part. The flutter suppression effect is numerically assessed via an iterative solution method, thus verifying CNABH’s feasibility. Results show that the CNABH can increase the panel's flutter critical boundary by 27.8%, outperforming a single nonlinear energy sink (NES) or an ABH, highlighting its advantages. Frequency analysis under varying boundary conditions clarifies that the panel flutter suppression performance of the CNABH critically depends on the frequency adaptability between the ABH part and the nonlinear part. Meanwhile, energy flow analysis reveals that the CNABH effectively integrates the energy sink characteristics of the nonlinear part and the ABH part, enabling the two parts to work synergistically to achieve rational energy distribution and efficient dissipation, thereby suppressing panel flutter more effectively. In summary, this work provides a new approach for panel flutter suppression and deepens the understanding of the nonlinear-ABH synergistic effect in aeroelastic control.