Combining nonlinear vibration absorbers and the Acoustic Black Hole for passive broadband flexural vibration mitigation

The Acoustic Black Hole (ABH) effect refers to a special vibration damping technique adapted thin-walled structures such as beams or plates. It usually consists of local decrease the structure thickness profile, associated thin viscoelastic coating placed in area minimum thickness. has been shown that structural design acts an efficient damper high frequency range, but not at low frequencies. This paper investigates how different types absorbers, linear and nonlinear, added primary system can improve performance beam ABH termination. In particular, conjugated effects Tuned Mass Damper (TMD), Nonlinear Energy Sink (NES), bi-stable NES (BNES), vibro-impact (VI-ABH) are investigated. Forced response random excitation computed time domain using modal approach combined with energy conserving numerical scheme. Frequency indicators defined characterize compare all solutions. simulation results clearly show proposed methods able damp efficiently flexural vibrations broadband manner. optimal tuning each solution is then investigated through thorough parametric study, showing optimize efficiency solution. TMD VI-ABH slight dependence on amplitude, while BNES have peak for moderate amplitudes.