切向流作用下含机械阻抗的声衬建模及分析  

Modeling and Analysis of Acoustic Liners with Mechanical Impedance under Grazing Flow

作　　者：倪臻 李旦望 纪良 周凯 NI Zhen;LI Danwang;JI Liang;ZHOU Kai(AECC Commercial Aircraft Engine Co.,Ltd.,Shanghai 200241,China;Institute of Rail Transit,Tongji University,Shanghai 201804,China)

机构地区：[1]中国航发商用航空发动机有限责任公司,上海200241 [2]同济大学铁道与城市轨道交通研究院,上海201804

出　　处：《噪声与振动控制》2024年第4期77-82,共6页Noise and Vibration Control

基　　金：国家科技重大专项资助项目(J2019-Ⅱ-0006-0026)

摘　　要：为提高声衬低频吸声能力,在声衬中引入机械阻抗结构,建立系统声阻抗模型并开展分析。首先,基于声传播方程,结合传递矩阵法建立均匀管道声传播模型。通过引入穿孔板及机械阻抗声学协调条件,进一步得到切向流作用下含机械阻抗的声衬阻抗模型。通过与现有文献及有限元法进行对比来验证给出方法的可靠性。对含机械阻抗的双自由度声衬开展数值分析,其结果表明,引入机械阻抗能显著提升声衬的低频吸声性能,声衬整体吸声量随流动马赫数的增大而先增大后减小,且较小的机械阻抗质量能够获取更好的低频吸声效果,低频吸声峰值频率随机械阻抗固有频率的增大而增大,峰值高度随机械阻抗阻尼的增大而减小。To enhance the low frequency sound absorption of acoustic liners,mechanical impedance is introduced to the acoustic liners,and the corresponding acoustic impedance model is established and analyzed.The transfer matrix method is adopted to model the one-dimensional sound propagation.The acoustic compatibility conditions for perforated panels and mechanical impedance panels are further introduced to model the impedance of acoustic liners under the grazing flow.The reliability of the proposed method is verified by comparing the results with those of existing literature and finite element method.Numerical study concerning a 2-DOF acoustic liner with mechanical impedance is carried out and shows that the sound absorption is firstly enhanced and then weakened with the increase of the Mach number,low frequency sound absorption is enhanced by a relatively small mass of the mechanical impedance,the frequency of the sound absorption peak increases with the increase of the natural frequency of the mechanical impedance,the height of the sound absorption peak decreases with the increase of the damping of the mechanical impedance.

关 键 词：声学 声衬 传递矩阵 机械阻抗 吸声 切向流 

分 类 号：O422.6[理学—声学]