基于低频吸声超构材料的复合消声器

Composite muffler based on low-frequency sound absorbing metamaterials

针对管道内低频噪声难以抑制的问题,基于亥姆霍兹共振腔阵列吸声板和穿孔管消声器组合,设计了一种复合式宽带消声器。首先利用有限元法仿真分析传统穿孔管消声器,发现中低频消声能力较差,通过嵌入亥姆霍兹共振腔阵列吸声板吸收中低频噪声。采用仿真与实验的方式研究吸声板的声学性能:在400∼1000 Hz频段内的平均吸声系数达到了0.88。然后对复合式消声器进行数值模拟及3D打印阻抗管实验测试对比:复合式消声器在400∼1718 Hz频率范围内的平均传递损失为18.15 dB。最终实现了管道内全频带噪声有效控制。

To solve the problem of low-frequency noise in pipeline, a composite broadband muffler is designed based on the combination of Helmholtz resonant cavity (HR) array sound-absorbing plate and perforated tube muffler. Firstly, the finite element method is used to simulate and analyze the traditional perforated tube muffler, and it is found that the noise attenuation ability is poor in the middle and low frequency. Simulation and experiment were used to study the acoustic performance of the sound absorption board: the average sound absorption coefficient reached 0.88 in the 400-1000 Hz frequency band. Then, numerical simulation and 3D printed impedance tube test were carried out for the composite muffler: the average transfer loss of the composite muffler was 18.15 dB in the frequency range of 400-1718Hz, and the effective control of full-frequency noise in the pipeline was finally realized.