Measurement of dispersion curves of circumferential guided waves radiating from curved shells: Theory and numerical validation

Mathieu Chekroun (1) , Jean-Gabriel Minonzio (2) , Claire Prada (3) , Pascal Laugier (2) , Quentin Grimal (2)

1 LAUM - Laboratoire d'Acoustique de l'Université du Mans
2 LIB - Laboratoire d'Imagerie Biomédicale [Paris]
3 ILL - Institut Laue-Langevin

A method is proposed to evaluate in a non-contact way the phase velocity dispersion curves of circumferential waves around a shell of arbitrary shape immersed in a fluid. No assumptions are made about the thickness or the material of the shell. A geometrical model is derived to describe the shape of the radiated wavefronts in the surrounding fluid, and predict the positions of its centers of curvature. Then the time-reversal principle is applied to recover these positions and to calculate the phase velocity of the circumferential waves. Numerical finite-difference simulations are performed to evaluate the method on a circular and on an elliptic thin shell. Different dispersion curves can be recovered with an error of less than 10%.

Mots clés: Acoustic waves; Geometrical acoustics; Ultrasound scanner; Waveguides; Stoneley waves; Rayleigh waves; Shell theory; Wave mechanics; Transducers; Lamb waves

Domaines: Acoustique [physics.class-ph]

Mathieu Chekroun, Jean-Gabriel Minonzio, Claire Prada, Pascal Laugier, Quentin Grimal. Measurement of dispersion curves of circumferential guided waves radiating from curved shells: Theory and numerical validation. Journal of the Acoustical Society of America, 2016, 139 (2), pp.790. ⟨10.1121/1.4941652⟩. ⟨hal-01305025⟩