压电分流声子晶体杆带隙调控研究

压电型声子晶体具有弹性波带隙特性，可用于噪声与振动控制。该文通过在环氧树脂杆上周期地布置含有负电容的压电分流单元，构造了压电声子晶体杆结构。为拓宽带隙，对此结构设计了3种元胞配置，运用传递矩阵法计算其带隙特性，并采用遗传算法对分流电路参数进行优化。理论与仿真结果表明，改变元胞中不同谐振频率的压电分流单元的个数，可以获得多个局域共振带隙，增强带隙可调谐性；运用算法优化可得到带隙调谐时分流电路参数值的最佳匹配，实现多个带隙的合并进而形成宽带，在不改变原有结构的基础上拓宽带隙。

Study on Band Gap Regulation of Phononic Crystal Rod with Piezoelectric Shunting

Owing to the property of elastic wave band gap, the piezoelectric phononic crystals have been used for noise and vibration control. In this paper, a piezoelectric phononic crystal rod structure is constructed by periodically arranging a piezoelectric shunt unit with negative capacitance on the epoxy resin rod. In order to expand the wide band gap, three cell configurations are designed for this structure, the transfer matrix method is used to calculate the band gap characteristics, and the genetic algorithm is used to optimize the shunt circuit parameters. The theoretical and simulation results show that by changing the number of piezoelectric shunt units with different resonance frequencies in the cell, multiple local resonance band gaps can be obtained, and the band gap tunability can be enhanced. By using the algorithm optimization, the best matching of the shunt circuit parameters can be obtained when the band gap is tuned, and the combination of multiple bandgaps can be realized and the wide band gap can be expanded without changing the original structure.