微薄膜超材料复合隔声结构的低频宽带隔声研究

Study on Micro-membrane Metamaterial Composite Structures for Low-frequency and Broadband Sound Insulation

在治理环境噪声方面低频隔声是一个难以解决的顽疾。随着声学超材料的发展,发现由薄膜微结构周期排列构成的轻质隔声材料具有优异的低频隔声性能。研究这种低频隔声材料与传统隔声材料的组合,通过设计这样一种复合结构实现覆盖低频到中高频的高效宽带隔声。在理论上推导出薄膜微结构的隔声量计算公式及简化公式,同时结合传统均质板的隔声理论,实现对复合隔声结构整体隔声的理论预测。通过对所设计样件的测试验证了理论模型的有效性,结果表明该复合结构具有高效的宽带隔声效果。该研究对低频宽带噪声控制具有较大应用价值。

In the process of controlling environmental noise,low-frequency sound insulation is a difficult problem.With the development of acoustic metamaterials,it is found that the lightweight sound insulation material composed of periodically arranged thin film microstructures has excellent sound insulation performance at low frequencies.In this paper,the combination of this low-frequency sound insulation material and traditional sound insulation materials is studied,and the corresponding composite structure is designed to realize broadband and high-efficiency sound insulation in low and midhigh frequency ranges.The calculation formula and simplified formula of the sound insulation of the thin film microstructure are deduced theoretically.Combining with the sound insulation theory of the traditional homogeneous plate,the theoretical prediction of the overall sound insulation of the composite sound insulation structure is realized.The validity of the theoretical model is verified by experimental tests on the designed samples.The results show that the proposed composite structure has broadband and high-efficiency sound insulation effects.This research has great application value for lowfrequency broadband noise control.