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2010, 8

M. El Allami, H. Rhimini, A. Nassim, M. Sidki

Application of the wavelet transform analysis to Lamb modes signals in plates

language: English

received 25.01.2010, published 29.04.2010

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The paper proposes a wavelet spectral analysis method of Lamb waves in thin isotropic plates. A numerical code is developed on the Comsol Multiphysics software to solve, by the finite element method, the equation of motion and determine the displacement field. The post processing of the obtained displacement field is done, on the Matlab software, by a method based on the wavelet transform (WT). The considered application aims to determine the dispersion curves of symmetric S0 and anti symmetric A0 Lamb modes of a plane steel plate. These curves are obtained by the WT of displacement field and are compared to the analytic curves. Several mother wavelets are tested showing that the complex mother wavelet Shan 1-1.5 gives the better agreement.

Keywords: lamb wave, ultrasound, finite element method, wavelets.

10 pages, 8 figures

Сitation: M. El Allami, H. Rhimini, A. Nassim, M. Sidki. Application of the wavelet transform analysis to Lamb modes signals in plates. Electronic Journal “Technical Acoustics”,, 2010, 8.


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Mhammed EL ALLAMI received master degree from Faculty of sciences, EL Jadida, Morocco. He has published 2 publications and communications on the finite element modelling of Lamb modes signals in plates. Presently he is a PhD student at Chouaib Doukkali University, El Jadida, Morocco.

E-mail: m.elallami(at)


Hassan RHIMINI received his master and PhD from Chouaib Doukkali University, EL Jadida, Morocco. He has published over 12 publications and communications on modelling of Lamb modes signals in plates. Hassan Rhimini is a PhD student at Chouaib Doukkali University, El Jadida, Morocco.

E-mail: hrhimini(at)


Abdelkarim NASSIM received his master from University of Pau, Pau, France and PhD from Chouaib Doukkali University, El Jadida, Morocco. He has published over 36 publications and communications on optics and wavelets. Abdelkarim Nassim is a Research Professor at Chouaib Doukkali University, El Jadida, Morocco.

E-mail: knassim58(at)


Mouncif SIDKI received his master from Paul Sabatier University, Toulouse, France and PhD from Sherbrooke University, Sherbrooke, Canada. He has published over 35 publications and communications on acoustics and modelling of ultrasound propagation. Mouncif Sidki is a Research Professor at Chouaib Doukkali University, El Jadida, Morocco

E-mail: sidkimouncif(at)