一种新型复合局域共振型声子晶体带隙特性

设计了一种新型复合局域共振型声子晶体，通过建立弹簧-质量块等效模型用于计算带隙的上下边界频率，同时结合有限元方法分析了该结构共振带隙的产生机理，根据带隙起止点频率处的位移模态研究了声子晶体的带隙特性。研究结果表明，该声子晶体结构在频率2 200 Hz附近产生三条完整带隙，其中一条是带宽达406.17 Hz的宽带隙。对于有限周期结构的声子晶体进行了传输特性仿真和隔声实验测试，在相同的频段内弹性波传播受到了阻碍。最后，对影响声子晶体带隙打开的几种因素进行分析，讨论了带隙上下边界调控机制。研究结果为声子晶体获得较宽的低频带隙提供了一种新的设计思路和方法。

Band gap characteristics of a new type of compound local resonance phononic crystal

In this paper, a new type of compound local resonance phononic crystal is designed, and the corresponding spring-mass equivalent model is established to calculate the upper and lower boundary frequencies of the band-gap. At the same time, the generation mechanism of the resonance band-gap is analyzed by the finite element method. The band-gap characteristics of the phononic crystal are studied according to the displacement modes at the start and end of the band-gap. The results show that the phononic crystal structure creates three complete band-gaps at a frequency of about 2 200 Hz, one of which is a broadband gap with a bandwidth of 406.17 Hz. The transmission characteristics of the phononic crystals with limited periodic structure are simulated and the sound insulation test is carried out, and the elastic wave propagation is hindered in the same frequency band. Finally, several factors affecting the band-gap of phononic crystal are analyzed, and how to regulate the upper and lower boundary of band-gap is discussed. The results provide a new idea and method for phononic crystal to obtain wide and low frequency band-gaps.