微穿孔板—二次余数扩散体复合结构的吸声特性仿真分析  

Study on Sound Absorption Characteristics of Composite Structure Made of Micro-perforated Panel and Quadratic Residue Diffuser

作　　者：林毅民 李盈利 LIN Yimin;LI Yingli(School of Traffic and Transportation Engineering,Central South University,Changsha 410075,China;Key Laboratory of Traffic Safety on Tracks,State Ministry of Education,Central South University,Changsha 410075,China;National and Local Joint Engineering Research Center of Safety Technology for Rail Vehicles,Central South University,Changsha 410075,China)

机构地区：[1]中南大学交通运输工程学院,长沙410075 [2]中南大学轨道交通安全教育部重点实验室,长沙410075 [3]中南大学轨道交通列车安全保障技术国家地方联合工程研究中心,长沙410075

出　　处：《噪声与振动控制》2023年第1期68-74,共7页Noise and Vibration Control

基　　金：国家自然科学基金资助项目(12172383)。

摘　　要：我国铁路建设规模逐渐扩大,列车运行速度不断加快,在运行过程中由于轨道不平顺、列车交汇等产生一系列噪声,而微穿孔板—二次余数扩散体复合结构可以用于解决轨道交通系统的噪声问题。首先通过Comsol有限元仿真对微穿孔板与7阶二次余数扩散体的复合结构进行吸声特性探究,结合已有的实验结果验证仿真方法的准确性。后续研究二次余数扩散体子背腔排列顺序对复合结构吸声特性的影响,发现只有保持二次余数扩散体腔体的对称性,才能使复合结构的吸声效果较好;探究二次余数扩散体子背腔折叠对复合结构吸声特性的影响,发现二次余数扩散体子背腔折叠对第一个吸声峰毫无影响,只对高阶谐振峰产生影响,背腔折叠的长度越大,第二个吸声峰发生频率越往高频移动;最后分析微穿孔板孔隙率、孔径及板厚对复合结构吸声特性的影响,结果表明微穿孔板的孔隙率及板厚主要影响吸声频率,随着孔隙率(板厚)变大,吸声结构的共振频率稍向高(低)频方向移动,而孔径主要对吸声性能起作用,孔径越小吸声峰越高。有关结论可为低频吸声结构设计提供参考。With the development of China’s railway construction and the increasing of speed of railway operation, a series of noise problems is generated in the process of railway operation due to the irregularity of track and the intersection of trains. The composite structure of micro-perforated plate and quadratic remainder diffusion can be applied to solve the noise problem of rail transit system. In this paper, the sound absorption characteristics of the composite structure of the microperforated plate and the 7-th order quadratic remainder diffuser are investigated by Comsol finite element simulation. The accuracy of the simulation method is verified by the existing experimental results. The effect of the order of the quadratic remainder diffuser on the sound absorption performance of the composite structure is studied. It is found that the sound absorption of the composite structure can be well improved only when the symmetry of the quadratic remainder diffuser is maintained. The influence of the back cavity folding of the quadratic remainder diffusing body on the sound absorption characteristics of the composite structures is investigated. It is found that the back cavity folding of the quadratic remainder diffusing body has no effect on the first sound absorption peak, but has the effect only on the high order resonant peak. The greater the length of the back cavity folding, the greater the frequency of the second sound absorption peak. Finally, the influence of porosity, pore diameter and thickness of the micro-perforated panel on the sound absorption characteristics of the composite structure is analyzed. Results show that the porosity and thickness of the micro-perforated panel mainly affect the acoustic frequency. With the increasing of the porosity(or thickness), the resonance frequencies of the sound absorbing structure slightly shift to high(or low) frequency direction. And the aperture effects mainly on the sound absorption performance, the smaller the aperture, the higher the absorption peak. This paper

关 键 词：声学 二次余数扩散体 微穿孔板 排列 折叠 

分 类 号：O422.4[理学—声学]