Computation of propagating and non-propagating guided modes in nonuniformly stressed plates using spectral methods

Abstract

This paper presents a numerical approach based on spectral methods for the computation of guided ultrasonic wave modes (i.e., Lamb and shear horizontal) in nonuniformly stressed plates. In particular, anisotropic elastic plates subjected to a normal stress profile, which varies nonuniformly over their thickness, are considered. The proposed approach computes the modeshapes and the full three-dimensional dispersion spectrum (i.e., real frequency, complex wavenumber). It therefore includes both propagating (real wavenumber) and non-propagating (complex wavenumber) modes. Furthermore, an approach for robustly post-processing the dispersion spectra in order to compute the group velocity of propagating modes is presented, which is based on a spectral quadrature method. Numerical results are presented for two case studies: (1) a bending profile in a fiber-reinforced graphite/epoxy plate, and (2) an exponential profile in a silver plate. The results show the computational efficiency (i.e., spectral convergence) of the proposed method compared to other existing approaches such as the sublayering and finite element methods.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 01, 2018
Source ID
10.1121/1.5040140

Entities

People

  • Arvin Ebrahimkhanlou
  • Brennan Dubuc
  • Salvatore Salamone

Organizations

  • Office of Naval Research
  • University of Texas at Austin

Tags

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Computational Fluid Dynamics (CFD)
  • Structural Dynamics.