Study of Lamb Waves for Non-Destructive Testing Behind Screens
Aix Marseille Univ, CNRS, Centrale Marseille, LMA, Laboratoire de Mécanique et d’Acoustique, Equipe Ondes et Imagerie, site d’Aix en Provence, Marseille, France
CEA CadaracheDEN/DTN/STCP/LIET (Laboratoire d’Instrumentation et d’Essais Technologiques), Saint Paul Lez Durance, France
Published online: 10 January 2018
The inspection and control of sodium-cooled fast reactors (SFR) is a major issue for the nuclear industry. Ultrasonic solutions are under study because of the opacity of liquid sodium. In this paper, the use of leaky Lamb waves is considered for non-destructive testing (NDT) on parallel and immersed structures assimilated as plates. The first phase of our approach involved studying the propagation properties of leaky Lamb waves. Equations that model the propagation of Lamb waves in an immersed plate were solved numerically. The phase velocity can be experimentally measured using a two dimensional Fourier transform. The group velocity can be experimentally measured using a short-time Fourier transform technique. Attenuation of leaky Lamb waves is mostly due to the re-emission of energy into the surrounding fluid, and it can be measured by these two techniques.
Key words: Group velocity / Leaky Lamb waves / Non-Destructive Testing (NDT) / Phase velocity / Re-emission / Sodium Fast Reactor (SFR) / Ultrasound
© The Authors, published by EDP Sciences, 2018
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (http://creativecommons.org/licenses/by/4.0/).