有限大背腔单层微穿孔板吸声体吸声特性研究  

Investigation on the absorption characteristics of single-layer micro-perforated panel absorber with finite-sized cavity

作　　者：郭文成[1,2] 闵鹤群[1,2] 

机构地区：[1]东南大学建筑学院,南京210096 [2]东南大学城市与建筑遗产保护教育部重点实验室,南京201096

出　　处：《南京大学学报（自然科学版）》2017年第4期681-685,共5页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(51408113);江苏省科技计划青年基金(BK20140623)

摘　　要：基于声有限元数值方法研究了有限大背腔单层微穿孔板吸声体的吸声特性.首先,建立了该类单层微穿孔板吸声体的有限元数值模型,并采用等效电路法对其准确性进行了验证.然后,基于已验证的仿真模型讨论了有限大背腔单层微穿孔板吸声体的斜入射吸声性能,以及背腔宽深比对其扩散场吸声系数的影响规律.结果显示,在正入射条件下,单层微穿孔板吸声体的吸声性能主要受到有限大背腔非切向模态的影响,而在斜入射条件下,主要受到切向模态的影响;不同入射角度的声波会激发有限大背腔不同的切向模态,从而改善单层微穿孔板吸声体的高频吸声性能;调整背腔宽深比能有效控制单层微穿孔板吸声体扩散场吸声系数曲线高频吸声峰的位置,并且存在最佳宽深比使其同时具有较高的吸声系数和较宽的吸声频带.本文可为噪声控制工程和室内声学设计提供有用的参考.In this paper,the absorption characteristics of a single-layer micro-perforated panel（MPP）absorber with finite-sized cavity are investigated according to the finite element method.Firstly,the numerical model of this kind of single-layer MPP absorber is established,and the accuracy of it is validated through the equivalent circuit method.Secondly,based on the validated finite element model,the sound absorption characteristics of the single-layer MPP absorber are discussed under oblique incidence conditions,and the influences of width-depth ratios of the finite-sized cavity on the diffuse field sound absorption coefficients of the absorber are also investigated.The results show that for a normal incidence condition,the sound absorption performances of the single-layer MPP absorber are mainly in-fluenced by the non-grazing modes of the finite-sized cavity,while for a grazing incidence condition,are mainly influenced by the grazing modes;in addition,the different grazing modes of the finite-sized cavity can be excited by the sound with different incidence angles,thus the absorption performance of the single-layer MPP absorber can be further enhanced;furthermore,the peak locations of the sound absorption coefficient of the single-layer MPP absorber at high frequencies can be effective controlled through tuning the width-depth ratio of the finite-sized cavity,and there is an optimum ratio that can makes the single-layer MPP absorber both have higher sound absorption coefficient and wider sound absorption bandwidth.This paper is supposed to provide some useful suggestions to noise engineering control and indoor acoustical design.

关 键 词：微穿孔板 数值仿真 斜入射 宽深比 

分 类 号：TU112[建筑科学—建筑理论] TU55