Lamb Waves and Dispersion Curves in Plates and It’s Applications in NDE Experiences Using Comsol Multiphysics

P. Gómez, J. P. Fernandez, and P. D. García
Hydro-Geophysics & NDE Modeling Unit
University of Oviedo
Mieres, Spain
Published in 2011

In this paper, a model for numerically obtaining lamb wave modes and dispersion curves in plates is presented. It is shown that COMSOL Multiphysics can be employed to simulate the behavior of guided waves in dispersive plates, which is useful for NDE applications.

A two dimensional steel plate (4x0.1 meters) is excited with a space-time impact point source. To model the point source, we use different possibilities included in COMSOL function’s library. Thirty probes are numerically implemented to measure the acceleration in thirty different positions of the surface of the plate (5cm spacing between them) and 50cm far from the impact point source. Once all features are described in the model, a time dependent study is performed by means of a simulation in the time domain. Results are checked against those in the frequency domain and presented. In both cases, numerical parameters have been manually adjusted for stability and convergence needs.