几何参数和声虹吸效应对薄膜声学超材料低频吸声性能的影响

The Effects of Geometric Parameters and Acoustic Siphon Effect on the Low-Frequency Sound Absorption Properties of Thin Film Acoustic Metamaterials

摘要: 针对低频噪声防治问题，本文设计了一种薄膜型声学超材料，质量块选用圆形质量块，分析几何参数对其吸声性能的影响，同时利用阻抗匹配原理解释了产生吸声峰的原因。研究结果表明：吸收峰主要来源于薄膜弹性振动；改变薄膜及附加质量的几何参数均会显著改变吸收峰的幅频特征，因此，可针对目标频谱特性，通过优化薄膜和附加质量的几何参数，有效改善薄膜声学超材料的吸声性能。引入声虹吸效应能提升了声学超材料低频吸声效果，为声学超材料结构设计与优化方面提供了解决思路。

Abstract: Aiming at the problem of low-frequency noise prevention and control, a thin-film acoustic metamaterial is designed in this paper. The circular mass block is selected as the mass block, and the influence of geometric parameters on its sound absorption performance is analyzed. At the same time, the impedance matching principle is used to explain the cause of the sound absorption peak. The results show that the absorption peak mainly comes from the elastic vibration of the film; changing the geometric parameters of the film and the additional mass will significantly change the amplitude-frequency characteristics of the absorption peak. Therefore, the sound absorption performance of the film acoustic metamaterial can be effectively improved by optimizing the geometric parameters of the film and the additional mass for the target spectral characteristics. The introduction of acoustic siphon effect can improve the low-frequency sound absorption effect of acoustic metamaterials, which provides a solution for the structural design and optimization of acoustic metamaterials.