A metamaterial for low-frequency vibration damping

The local resonant phononic crystal structure is significantly smaller than the control wavelength so it is of major importance for controlling the sound field in the low-frequency band. However, lightweight and small local resonant phononic crystal structures still present a great challenge. In this paper, we propose a metamaterial for low-frequency damping. The band structures and eigenmodes are calculated using the finite element method, and the generation mechanism of the resonant band gap is analyzed. The results show high transmission losses in the band gaps of 26.8–30.8 Hz and 33.7–180.1 Hz. In addition, the effect of geometric parameters on the bandgap frequency is discussed, and the control of the low-frequency bandgap can be achieved by adjusting the geometric parameters. The results of the study provide a new design idea for obtaining phononic crystal structures with low-frequency band gaps.