A Local Resonance Metamaterial For Vibration Reduction

Abstract

The reduction of low-frequency vibration and noise has been a challenging task. A design of locally resonant metamaterial plate is proposed to overcome the difficulty of the low-frequency vibration reduction. The low-frequency vibration characteristics of the proposed structure are investigated numerically by the finite element method. The formation mechanism and influencing factors of the band gap in low-frequency vibration are analyzed, and the structure is optimized on this basis. It is found that the interaction between the local resonances and the traveling wave modes in the plate results in the formation of the locally resonant band gap, whose bandwidth depends on interaction strength and can be modulated by changing structural material parameters. The optimized structure can open lower and multiple band gaps and improve the attenuation performance of vibration wave. The results show that, the structure can open two complete range of vibration reduction with the width of 13Hz and 27 Hz in the frequency range below 250 Hz, and the starting frequency is as low as 180 Hz. The finite model with the number of 36 resonators has obvious effect to reduce vibration in the bandgap. The structure has potential application prospects.