Roy Tuhin, Guddati Murthy N
Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina, 27607, USA.
J Acoust Soc Am. 2021 Feb;149(2):972. doi: 10.1121/10.0003430.
A suite of methodologies is presented to compute shear wave dispersion in incompressible waveguides encountered in biomedical imaging; plate, tube, and general prismatic waveguides, all immersed in an incompressible fluid, are considered in this effort. The developed approaches are based on semi-analytical finite element methods in the frequency domain with a specific focus on the complexities associated with the incompressibility of the solid media as well as the simplification facilitated by the incompressibility of the surrounding fluid. The proposed techniques use the traditional idea of selective reduced integration for the solid medium and the more recent idea of perfectly matched discrete layers for the surrounding fluid. Also, used is the recently developed complex-length finite element method for platelike structures. Several numerical examples are presented to illustrate the practicality and effectiveness of the developed techniques in computing shear wave dispersion in a variety of waveguides.
本文提出了一套用于计算生物医学成像中不可压缩波导内剪切波频散的方法;在此研究中考虑了板、管和一般棱柱形波导,它们都浸没在不可压缩流体中。所开发的方法基于频域中的半解析有限元方法,特别关注与固体介质不可压缩性相关的复杂性以及周围流体不可压缩性带来的简化。所提出的技术对固体介质采用传统的选择性减缩积分思想,对周围流体采用最新的完全匹配离散层思想。此外,还采用了最近为板状结构开发的复长度有限元方法。给出了几个数值例子来说明所开发技术在计算各种波导内剪切波频散方面的实用性和有效性。