双面框架式板型声学超材料的低频隔声特性研究

Study on Low Frequency Sound Insulation Characteristics of Double-Sided Framed Plate Acoustic Metamaterials

摘要: 根据经典的质量定律，传统的轻量化结构在低频时通常无法提供良好的隔声性能。针对低频声波的控制，本文提出了一种具有双面框架的板型声学超材料。利用有限元方法计算了其声传输损失和色散关系，并结合振动模态详细分析了该超材料结构形成低频隔声的物理机理；研究了超材料结构的几何参数对其声传输损失的影响。结果表明：所设计的超材料结构能够实现低频宽带隔声效果，隔声峰频率主要受谐振器的固有频率的影响；隔声谷由谐振器和基体板的质量比决定。框架的对称分布，可以实现双峰耦合，拓宽隔声峰频带。本文提出的框架式板型声学超材料为低频宽带降噪领域的声学超材料结构的设计提供了一定的参考价值。

Abstract: According to the classical mass law, conventional lightweight structures usually do not provide good sound insulation at low frequencies. A plate-type acoustic metamaterial with double-sided frames was proposed for low-frequency sound wave control. The proposed metamaterial sound transmission loss and dispersion curve were calculated using the finite element method. The physical mechanism of sound insulation formation was analyzed using vibration modes. The influence of the geometrical parameters of the metamaterial structure on the sound insulation performance was explored. The results show that the designed metamaterial structure can achieve low-frequency broadband sound insulation. The sound insulation peak frequency is mainly affected by the natural frequency of the resonator mass, and the sound insulation dip is determined by the mass ratio of the resonator to the thin plate. The symmetric distribution of the frame can achieve double-peak coupling and broaden the acoustic insulation peaks. The framed plate acoustic metamaterial proposed in this paper provides some reference value for the design of acoustic metamaterial in the field of low-frequency broadband noise reduction.