Abstract: The finite element model of sheet-shaped phononic crystals was established with Patran software, and the results of simulation showed that the band gap was between 164 and 353 Hz. A simplified model of Z-mode of bending vibration for sheet-shaped phononic crystals was proposed. The effect of material parameters, such as the density of scatter, the thickness of coating, and the constraint condition on the band gap was analyzed. The phononic crystal samples made of acrylic, steel, and silicone were provided, and their transmission characteristics were tested experimentally. The result shows that there are obvious band gaps below 2 000 Hz, and the attenuation of vibration amplitude can exceed 40 dB. This work may provide a reference for application of phononic crystals to vibration attenuation of sheet-shaped component parts of automotives.

Key words: acoustics , phononic crystal , bend vibration , finite-element method , transfer characteristic test

摘要： 利用Patran软件建立薄板声子晶体的有限元模型，通过仿真计算，可以得到一定带隙频率在164～ 353 Hz之间。提出薄板弯曲振动的Z模式简化模型，分析基体密度等材料参数、包覆层厚度及约束对带隙的影响。利用亚克力、钢、硅胶材料制作声子晶体样件，并进行传输特性实验，得出2 000 Hz的频率范围内存在明显的带隙，且振动衰减幅值达到40 dB以上，为声子晶体在车用板状材料减振的具体应用提供依据。

关键词: 声学, 声子晶体, 弯曲振动, 有限元仿真, 传输特性试验