LOW-FREQUENCY VIBRATION SUPPRESSION USING A PIEZOELECTRIC METAMATERIAL BEAM WITH TUNABLE BAND GAP

Acoustic metamaterials have been widely studied in recent years. Generally, when a passive acoustic metamaterial for vibration suppression is designed and manufactured, its structure is difficult to adjust, and the corresponding vibration reduction characteristics are also difficult to change, which greatly limits their vibration isolation ability in complex dynamic vibration environments. In this study, we propose a piezoelectric metamaterial (PMM) beam with a tunable band gap based on Kirchhoff's law. The structure is composed of piezoelectric ceramic materials, PMMA (Polymethyl Methacrylate), and aluminum, in which the piezoelectric ceramic materials with inductor-resistance-capacitor (LRC) shunting circuits utilize electromagnetic oscillation and electromechanical coupling properties to form a tunable local resonance (LR) band gap inside the metamaterial beam. The dispersion curve of the PMM beam was calculated using the transfer matrix method. Firstly, the energy bands of PMM beams with different compositions were compared, which demonstrated that the proposed structure had a lower frequency and wider band gap. Subsequently, the values of inductance, resistance, and capacitance in the LRC shunting circuit were changed to study the effects of its parameters on the band gap starting frequency, cutoff frequency, and bandwidth. The proposed piezoelectric metamaterial beam provided a new idea for suppressing variable vibration frequencies in the environment.