封闭式背腔微穿孔板吸声结构  

Micro-perforated Panel Absorber with Sealed Back Cavity

作　　者：吴腾 刘秀娟[1] WU Teng;LIU Xiujuan(School of Mechanical Engineering,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学机械工程学院,银川750021

出　　处：《噪声与振动控制》2022年第2期79-84,共6页Noise and Vibration Control

基　　金：宁夏自然科学基金资助项目(2018AAC03034)。

摘　　要：为提高微穿孔板吸声体的吸声性能,提出一种宽频带封闭式背腔微穿孔板吸声结构。使用薄膜封闭背腔中的特定气体,改变背腔声抗,配合参数合理的微穿孔板,能够提升低频吸声性能并有效拓宽吸声频带。基于声电类比法推导该吸声体的吸声系数计算方法,通过有限元仿真以及阻抗管实验对理论计算结果进行验证,最后探究背腔气体、微穿孔板振动和薄膜厚度对吸声性能的影响。结果表明,背腔气体对吸声性能有显著影响,当在背腔中填充六氟化硫时,能提升该结构的低频吸声性能,但使吸声带宽变窄;当在背腔中填充氦气时,其法向吸声系数在240 Hz~4 300 Hz频率范围内大于0.5。To improve the sound absorption performance of the traditional micro-perforated panel(MPP) absorbers, a wideband MPP absorber with sealed back cavity is proposed. In the new absorber, membrane is used to seal the specific gas in the back cavity to change its acoustic reactance. With the reasonable parameters of the MPP, the low frequency sound absorption performance of the absorber can be greatly improved and the sound absorption band of the absorber is widened effectively. The calculation method of the sound absorption coefficient of the absorber is formulated based on acoustoelectric analogy approach. The calculation results are verified by finite element simulation and experiment. Finally, the effect of specific gas in the back cavity, MPP vibration and membrane thickness on the sound absorption performance are explored. Results indicate that the gas in the cavity has an important influence on the sound absorption performance of the absorber. With the back cavity filled with sulfur hexafluoride, the low frequency sound absorption performance of the new absorber is better than that of the traditional absorber, however, its sound absorption band is narrower. While the back cavity is filled with helium, its normal sound absorption coefficient is greater than 0.5 within the frequency range of 240 Hz-4 300 Hz.

关 键 词：声学 宽频带 微穿孔板 封闭背腔 气体 吸声系数 

分 类 号：TU112.3[建筑科学—建筑理论] TK413.47[动力工程及工程热物理—动力机械及工程]