韧带结构对手性超材料弹性波传播带隙的影响∗

摘要

A hexagonal chiral cellular metamaterials was taken for example,the focus was put on investigating that the effect of microstructure ligament dynamic characteristics on band gap of elastic wave propagation in such chiral metamaterials.Firstly,a model of natural frequencies of ligament was established based on consider-ing the elastic supports existing between the ligament and the node.Then,the formation mechanism of elastic wave propagation band gap existing in chiral periodic structure metamaterials was explored.The results show that,compared with the fixed support,the natural frequency was lower when the ligament was elastic suppor-ted,and ligament is shorter,it is more sensitive to the elastic support.The formation mechanism of elastic wave propagation band gap was that the vibration was localized to a small number of ligaments.The results im-ply that we can achieve versatile control band gap structure by adjusting connect elasticity of ligaments and by changing their mass distribution.%针对手性周期结构超材料，重点研究材料内部微结构韧带的动态特性对手性超材料中弹性波传播带隙的影响。建立了考虑韧带与节点环之间弹性联接的韧带固有频率的计算模型，在此基础上，探索弹性波在手性周期结构超材料中传播带隙的形成机理及其与韧带性能参数和尺寸之间的关联。结果表明，手性结构中弹性支承韧带的频率比其简化为两端固支的要低，韧带越短，对弹性支承特性越敏感；超材料中少数韧带振动的局部化导致的能量耗散是抑制弹性波传播的根源，通过改变韧带的联接弹性和质量分布可以实现对超材料中弹性波传播特性的主动调控。