用于变压器整数阶谐频噪声的吸声超表面研究

Research of Acoustic Absorption Metasurface for Transformer Integer-order Harmonic Noise

利用共振型声学超表面吸声是近年来噪声控制的研究热点,然而其狭窄的吸收峰限制了进一步应用。针对电磁噪声在中低频噪声峰分布呈现倍数关系的特点,基于Visco-Thermal长直管吸声原理设计了六棱柱状的共面迷宫腔声学超表面单元结构,厚度仅为波长的1/137,可以用一种结构实现对多个噪声峰值的吸收。利用不同单元结构的并联,实现了对更多噪声峰值的覆盖。以变压器噪声为例,用并联的共面迷宫腔声学超表面结构实现对800 Hz以下所有整数阶谐频噪声的吸收,分析了结构参数对吸声效果的影响规律并进行了原理性实验验证。

In recent years,the use of the sound absorption of resonant acoustic metasurface is a hot spot research in noise control. However,its narrow absorption peak limits further applications.Aiming at the characteristic that electromagnetic noise which has multiple noise peak in the medium and low frequency,a hexagonal prism-shaped coplanar labyrinth cavity acoustic metasurface unit structure is designed on the basis of Visco-Thermal long straight pipe sound absorption principle and the thickness is only 1/137 of the wavelength. One structure can be used to absorb multiple noise peaks. The coverage of multiple noise peak is achieved by using the parallel connection of different unit structures.The transformer noise is taken as an example,the parallel coplanar labyrinth cavity acoustic metasurface structure is used to achieve absorption of all integer-order harmonic noises below 800 Hz.The influence of structural parameters on the acoustic absorption effect is analyzed and the principle experimental verification is performed.