可调谐局域共振梁带隙模型改进

摘要

局域共振声子晶体具有弹性波带隙特性,可用于结构振动与噪声控制.通过引入压电分流阵列也可以在基体结构形成弹性波带隙,尤其是谐振分流电路可以产生局域共振带隙.而且,通过调节分流电路参数可以方便地改变其局域共振带隙特性.研究了含压电分流阵列的局域共振梁带隙计算建模方法,指出了传统带隙模型的不足,并提出了改进模型.利用传递矩阵法计算了传统模型和改进模型弯曲波传播常数,比较了两种模型对带隙预测的差异,发现传统模型在局域共振带隙内形成了较大误差,利用改进模型可以大大提高局域共振带隙的预测精度.%Locally resonant crystals possess elastic wave band-gaps, which can be used for vibration and noise control of structures.By introducing piezoelectric shunting arrays in host structures, band gaps can also be generated.Particularly, locally resonant gaps can be induced by resonant shunting circuits.Moreover, the properties of locally resonant gaps are conveniently tuned by modifying the circuit parameters.The modeling method for beams with piezoelectric shunting arrays was investigated, where the deficiency of the conventional model was pointed out and an improved model was proposed.By using the transfer matrix method, the propagation constants of the conventional and improved models were predicted and compared.The results demonstrate that the conventional model presents great errors.Hence, the improved model effectively boosts the accuracy of locally resonant gap prediction.