低频机械波在传播过程中穿透力强,难以衰减,特别是次声频段的机械波易与机体器官发生共振,对身体造成危害。为了实现对低频机械波的有效控制,解决现代工业生产和生活中普遍存在的噪声污染问题,结合最近十几年发展起来的声子晶体和声学超材料,系统地总结和论述通过声子晶体和声学超材料解决低频振动噪声问题的新方法。归纳和总结典型的低频振动噪声来源和对其进行控制方面存在的一些困难,介绍低频振动噪声的危害。重点概括基于声子晶体禁带特性实现低频振动噪声被动控制的相关研究工作,主要介绍通过亚波长尺寸特征的杆、薄板和薄膜类结构来实现低频振动和噪声衰减的具体方法和效果。在声学超材料的理论框架下,讨论薄膜类结构在低频振动噪声衰减中的应用及其优缺点。通过结合实际工程需要和最新研究动态,对这一领域存在的问题和后续发展趋势进行总结。研究对推动声子晶体和声学超材料在工程实践中的应用具有一定的引导意义。
The low-frequency mechanical wave has stronger penetration capability in dissemination process, so it is hard to be attenuated. Especially in infrasound range, the mechanical wave could resonance with body organs easily, and causing harm to health. In order to effectivly control the low-frequency mechanical wave, the solution for noise pollution problems in modern industrial production and daily life is given, by combining with the phononic crystals and acoustic metamaterials that have been developed in last decade. New methods for low-frequency vibration and noise reduction based on phononic crystals and acoustic metamaterials are systematically summarized and discussed. Typical sources of low-frequency vibration and noise, the existence difficulties to control it, and the harms to human body are summarized. The related works that passively control the low-frequency vibration and noise based on acoustic band gap characteristics of photonic crystal are summarized. Particularly, the specific methods and effects to achieve low-frequency vibration and noise attenuation by rod, plate and membrane structures with subwavelength size characteristics are reviewed. In the framework of the acoustic metamaterials, the applications of membrane-type structures in low-frequency vibration and noise attenuation, its advantages and disadvantages are discussed. Through a combination of practical engineering and the latest research developments, the problems still exist in this field and future trends are summarized. The result has some guiding value to promot the application of phononic crystals and acoustic metamaterials in engineering practice.