点击次数：

所属单位：航空学院

发表刊物：JOURNAL OF SOUND AND VIBRATION

关键字：Flexural wave Acoustic black hole Focalization Ray trajectories

摘要：An Acoustic Black Hole (ABH) indentation embedded in thin-walled structures has been proved remarkably useful for broadband flexural wave focalization, in which the phase velocity of the flexural waves and the refractive index of the media undergo gradual changes from the outside towards the center of the indentation. A generalized two-dimensional ABH indentation can be defined by three geometric parameters: a power index, an extra thickness and a radius of a plateau at the indentation center. The dependence of the energy focalization on these parameters as well as the energy focalization process is of paramount importance for the understanding and design of effective ABH indentations. This work aims at investigating the energy focalization characteristics of flexural waves in such generalized ABH indentations. The calculation of the flexural ray trajectories is conducted to reveal and analyze the wave propagation features through numerical integration of the eikonal equation from the Geometric Acoustics Approximation (GAA). The theoretical results are verified by both experiment using wave visualization technique based on laser acoustic scanning method and finite element (FE) simulations. Finally, the influence of the geometric parameters on the flexural wave focalization characteristics in ABH indentations is discussed in detail. (C) 2017 Elsevier Ltd. All rights reserved.

ISSN号：0022-460X

是否译文：否

发表时间：2018-03-17

合写作者：黄薇,裘进浩,Cheng, Li

通讯作者：季宏丽