Elastic wave propagation in perforated plates with tetrad elliptical structural hierarchy: Numerical analysis and experimental verification

摘要

In this paper we proposed a hierarchical structure with tetrad elliptical patterns in perforated plates. It is discovered that the introduction of structural hierarchy can enhance wave energy localization and introduce additional band gaps in 3d plates, in which elastic wave cannot propagate. However, if the hierarchical level increases further, extra vibration modes will be introduced, which may lead to the narrowing or vanishing of the band gaps. Parametric studies have been carried out to illustrate the possibility of tuning band gaps with geometric variation, and the results also demonstrate that the effect of structural hierarchy is not only limited to one specific geometric configuration. In this study, the finite element analysis and band diagram analysis are used for investigation. Moreover, experimental tests have been conducted for level-1 and level-2 perforated plates for comparison, and excellent agreement between numerical analysis and experimental tests has been achieved, which also shows the feasibility of applying this strategy in structural design and other vibration mitigation applications. (C) 2019 Elsevier Ltd. All rights reserved.