错位微缝板吸声性能研究  

Acoustic performance of a micro-staggered structure

作　　者：蒋从双[1] 李贤徽[1] 邢拓 JIANG Congshuang;LI Xianhui;XING Tuo(Beijing Key Laboratory of Environment Noise and Vibration,Beijing Municipal Institute of Labor Protection,Beijing 100054,China)

机构地区：[1]北京市劳动保护科学研究所,环境噪声与振动北京市重点实验室,北京100054

出　　处：《振动与冲击》2020年第14期69-74,79,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(11604015);北京市自然科学基金(1172007);北京市劳动保护科学研究所改革与发展经费自立课题。

摘　　要：目前,微穿孔板和微缝板吸声理论成熟、应用广泛。一般,薄板确保了其具备良好的吸声性能,却限制了其工程应用范围。错位微缝板融合了微穿孔板和微缝板,由双层板错位交叠而成,每层板由一系列微缝组成,上下两层微缝交错处形成微孔。交错后的微缝只在交汇的微孔处是通透的,交错形成的微孔仅是一个微孔截面,几何厚度为零。对错位微缝板进行黏热声学仿真,得到结构的相对声阻抗和吸声系数与实验数据一致性较好。仿真分析表明,结构的微孔截面处声压梯度和空气粒子振动速度最大,其黏热声能耗散主要集中在微孔截面的边界处,错位微缝板的厚度对吸声性能的影响远小于微穿孔板和微缝板,可以在厚板上实现较好的吸声性能。Now, the acoustic theory for the micro-perforated plate(MPP) and micro-slitted plate(MSP) is mature and its application is widespread. Thin plate ensures good acoustic performance but restricts the applications in practical engineering. A micro-staggered structure(MSS) was proposed, which was a combination of MPP and MSP, and was made by overlapping and staggering two layers of plates. Each layer was constituted by arranging an array of strip-shaped sheets, each other separated with a certain space. Micro slits were formed at between those strip-shaped sheets and micro apertures were constructed at the intersection of those micro slits. The micro slits were open to the air completely on one side but blocked to the sheets on the other side. The micro apertures were just a layer of cross contour, its shape was defined by the two layers of plates and its geometrical thickness was equal to zero. A thermoviscous acoustics simulation on the MSS was conducted. A good agreement between the simulated results and the experimental data for the acoustic impedance and sound absorption coefficient was achieved. The simulation shows that the maximum pressure gradient and particle velocities are on the cross contour and the thermal-viscous energy loss is concentrated at the boundary of the cross contour. It also demonstrates the effect of plate thickness on the acoustic performance of MSS is much less than that of MPP and MSP, which helps to achieve good acoustic properties on a thick plate.

关 键 词：错位微缝板(MSS) 微穿孔板(MPP) 微缝板(MSP) 

分 类 号：O429[理学—声学] TB535+.1[理学—物理]