迷宫式声学超材料降噪分析

王帅杰¹，徐传燕^1*，黄显利¹，李永生²，邢其森¹，刘永利¹，刘润达¹

1.山东交通学院汽车工程学院，山东 济南  250357；2.山东省高速养护集团有限公司，山东 济南  250032

摘要：为解决传统降噪系统效率低、设计复杂、噪声控制效果不稳定等问题，基于声学超材料设计一种迷宫式超材料结构，采用COMSOL软件仿真分析迷宫式声学超材料对声波传播方向及不同频率声波的影响，通过试验验证超材料个数对噪声声压级的影响。仿真结果表明：迷宫式声学超材料改变声波的传播方向，形成异常反射以降低噪声声压级；超材料厚度与声波频率有关，可针对不同频率的噪声设计超材料结构，实现精准降噪。试验结果表明：声波频率为2 kHz时，采用迷宫式声学超材料可使声压级均方根从83.47 dB降至74.85 dB，噪声明显降低；随着超材料个数增加，声压级均方根持续降低，降噪效果越好，但超材料个数过多导致整体结构质量增大，建议实际应用时选择一组（2个）或两组（4个）超材料，此时降噪效果较佳。

关键词：声学超材料；噪声控制；异常反射；声压级均方根

Noise reduction analysis of a maze-type acoustic metamaterial

WANG Shuaijie¹, XU Chuanyan^1*, HUANG Xianli¹, LI Yongsheng², XING Qisen¹, LIU Yongli¹, LIU Runda¹

1.School of Automotive Engineering,Shandong Jiaotong University, Jinan 250357, China;

2.Shandong High Speed Maintenance Group Co., Ltd., Jinan 250032, China

Abstract: To solve the problems of low efficiency, complex design, and unstable noise control in traditional noise reduction systems, a maze-type metamaterial structure is designed based on acoustic metamaterials. The COMSOL software is used to simulate and analyze the influence of the maze-type acoustic metamaterials on the propagation direction of sound waves and sound waves of different frequencies. The influence of the number of metamaterials on the noise sound pressure is verified through experiments. The simulation results show that the maze-type acoustic metamaterials change the propagation direction of sound waves, forming abnormal reflection to reduce the noise sound pressure; the thickness of the metamaterials is related to the frequency of sound waves, and the metamaterial structure can be designed for different frequency noises, which can achieve precise noise control. The experimental results show that when the sound wave frequency is 2 kHz, using maze-type acoustic metamaterials can reduce the root mean square of sound pressure level from 83.47 dB to 74.85 dB, and the noise is significantly reduced; as the number of metamaterials increases, root mean square of the sound pressure level continues to decrease, and the noise reduction effect is better, but too many metamaterials lead to an increase in the overall mass of the, it is recommended to choose a group (2 pieces) or two groups (4 pieces) when used in practice, and the noise reduction effect of metamaterials is better at time.

Keywords: acoustic metamaterial; noise control; abnormal reflection; root mean square of sound pressure level