Acoustic Propagation Characteristics of Metamaterials With Tubular Structures

Abstract

To generate acoustic waves with abnormal transmission characteristics different from those of traditional natural acoustic materials, we studied the propagation of acoustic waves in resonant phononic crystals. We identified the vibration mechanism of 2D three-component locally resonant phononic crystals. Using the finite element software COMSOL, an acoustic propagation model of a tubular structure based on acoustic metamaterials was constructed, and the local resonance characteristics of the acoustic waves and the original cells were used to simulate the propagation characteristics of the acoustic waves. We found that after low-loss wavefront propagation, most of the incident acoustic waves were absorbed by the model and reconverged with the outgoing acoustic waves on the other side of the model. Acoustic metamaterials with different layers emit acoustic waves at different locations, and thus, the propagation distance can be controlled by the design of the acoustic metamaterials. In addition, the propagation characteristics of the acoustic waves tend to be better at frequencies close to the resonance frequency. Because of the flexibility and the controllability of the acoustic metamaterials, the structure can be designed according to the actual situation to achieve the resonance frequency needed to propagate acoustic signals. This can improve the efficiency of acoustic propagation and provide new ideas for actual underwater acoustic source detection and acoustic communication.