Guided wave mode selection for inhomogeneous elastic waveguides using frequency domain finite element approach

Vamshi Krishna Chillara; Baiyang Ren; Cliff J Lissenden

doi:10.1016/j.ultras.2015.12.007

Guided wave mode selection for inhomogeneous elastic waveguides using frequency domain finite element approach

Ultrasonics. 2016 Apr:67:199-211. doi: 10.1016/j.ultras.2015.12.007. Epub 2015 Dec 19.

Authors

Vamshi Krishna Chillara¹, Baiyang Ren², Cliff J Lissenden²

Affiliations

¹ Department of Engineering Science and Mechanics, The Pennsylvania State University, 16802 PA, United States. Electronic address: vamshik.iitm007@gmail.com.
² Department of Engineering Science and Mechanics, The Pennsylvania State University, 16802 PA, United States.

PMID: 26746160
DOI: 10.1016/j.ultras.2015.12.007

Abstract

This article describes the use of the frequency domain finite element (FDFE) technique for guided wave mode selection in inhomogeneous waveguides. Problems with Rayleigh-Lamb and Shear-Horizontal mode excitation in isotropic homogeneous plates are first studied to demonstrate the application of the approach. Then, two specific cases of inhomogeneous waveguides are studied using FDFE. Finally, an example of guided wave mode selection for inspecting disbonds in composites is presented. Identification of sensitive and insensitive modes for defect inspection is demonstrated. As the discretization parameters affect the accuracy of the results obtained from FDFE, effect of spatial discretization and the length of the domain used for the spatial fast Fourier transform are studied. Some recommendations with regard to the choice of the above parameters are provided.

Keywords: Finite elements; Frequency-domain; Guided waves; Ultrasonics.