轨道结构中零群速度导模的动态行为。

Dynamic behavior of a zero-group velocity guided mode in rail structures.

作者信息

Wu Yuning, Zhang Keping, Zhang Peng, Zhu Xuan, Popovics John S

机构信息

Department of Civil & Environmental Engineering, University of Utah, Salt Lake City, Utah 84112, USA.

Department of Civil & Environmental Engineering, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801,

出版信息

JASA Express Lett. 2023 Oct 1;3(10). doi: 10.1121/10.0021186.

DOI:10.1121/10.0021186

PMID:37782265

Abstract

Important characteristics of a zero-group velocity (ZGV) mode in a standard rail are investigated through numerical simulation and experiment. First, the semi-analytical finite element analysis is implemented to compute dispersion curves for the rail structure and the first ZGV point is identified. Backward waves are identified through opposing senses of group and phase velocities. Next, a time-dependent finite element model is used to understand the dynamic response of the rail. Finally, experimental measurements confirm that ZGV modes in rail structures are formed through interferences between two opposite-traveling waves, which is analogous to the S1-S2b ZGV Lamb mode in plate structures.

摘要

通过数值模拟和实验研究了标准轨道中零群速度（ZGV）模式的重要特性。首先，实施半解析有限元分析来计算轨道结构的色散曲线，并确定第一个ZGV点。通过群速度和相速度的相反方向识别反向波。接下来，使用时变有限元模型来了解轨道的动态响应。最后，实验测量证实，轨道结构中的ZGV模式是由两个反向传播波之间的干涉形成的，这类似于板结构中的S1-S2b ZGV兰姆模式。