一维声子晶体的传输特性

Transfer Characteristic of One-dimensional Phononic Crystal

推导出一维声子晶体的转移矩阵,研究了一维声子晶体的传输特性。得出:声波在一维声子晶体中传播时会出现一系列禁带,各级禁带的频率中心是等间隔的,各级禁带的频率宽度是相等的。相邻禁带的频率中心的间隔随介质的厚度成反比变化,禁带的频率宽度随介质的厚度成反比变化。禁带的频率宽度随两介质声阻抗的差值的减小而减小。

The transfer matrix of the one-dimensional phononic crystal is derived. The transfer characteristic of the one-dimensional phononic crystal is studied. The sound wave in the phononic crystal can appear a series of forbidden bands. Each frequency center of the forbidden band has the same distance. Each forbidden band has the equal frequency width. Neighboring frequency center distance of the forbidden band follows the medium thickness to become the inverse ratio change. The frequency width follows the medium thickness to become the inverse ratio change. The frequency width of the forbidden band reduces along with the differences of two sound impedance reduces.