侧面周期嵌入空气柱薄板中兰姆波带隙研究(英文)

Lamb waves in thin plates with the surfaces parallel to the periodically inserted void cylinders

提出一种在薄板侧面周期嵌入空气柱的一维声子晶体模型,数值计算了兰姆波在该周期结构声子晶体中的传播特性.结果表明:由布拉格散射引起的第一完全禁带只在一定的占空比范围内存在,分别改变空气柱半径和晶格常数,禁带宽度可调且达到最大值时的占空比值基本相同.将占空比匹配的该一维声子晶体接合构成复合结构,低阶兰姆波完全禁带宽度因各组分兰姆波完全禁带交叠相加而显著增大.

The authors study numerically the propagation of Lamb waves in one-dimensional periodic thin plates consisting of a row of void cylinders inserted periodically in the host material. The surfaces of the plates are parallel to the axis of periodicity. The lowest Lamb wave complete band gap of the composite thin plates originates mainly from the Bragg scattering and only exist in some filling ratio range. The band gap reach its maximum width almost in the same filling ratio for the cylinder radius and lattice spacing are respectively employed as variables. We show that the band gap has a good adjustability and can be substantially enlarged by using multiple periodic systems which consist of several pieces of periodic structure with different filling fraction.