Characterization of Low-Frequency Broadband Vibration Damping with an ABH-TMD Vibrator Based on the Acoustic Black Hole Principle

The utilization of tuned mass dampers (TMDs) is subject to numerous restrictions. In general, the control performance of a TMD is limited by the ratio of the mass block to the effective mass of the main structure (mass ratio). These dampers also require precise tuning to the required target frequency to absorb the host structure’s vibrational energy. Due to their unique geometric gradient forms, acoustic black hole (ABH) structures can slow the propagation speed of bending waves and concentrate them at the apex, thereby significantly enhancing the suppression of broadband vibration. In this paper, we combine the above two methods to form a single novel device named ABH-TMD. Firstly, a mechanical model of the proposed device is established. The bending-wave control equation is derived, followed by a numerical analysis and experimental tests for further verification. Secondly, a series of numerical simulations are conducted. The response of the controlled beam is determined based on time histories and the frequency domain. Lastly, parameter analysis is carried out to investigate the control’s effectiveness. Based on the numerical and experimental results, we conclude that the proposed ABH-TMD can successfully concentrate elastic waves, thereby surpassing the traditional TMD under broadband frequency conditions.