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  Estonian Journal of Engineering

ISSN 1736-7522 (electronic)  ISSN 1736-6038  (print)

 An international scientific journal
Formerly: Proceedings of the Estonian Academy of Sciences Engineering
(ISSN 1406-0175)
Published since 1995

Estonian Journal of Engineering

ISSN 1736-7522 (electronic)  ISSN 1736-6038  (print)

 An international scientific journal
Formerly: Proceedings of the Estonian Academy of Sciences Engineering
(ISSN 1406-0175)
Published since 1995

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Separation of Lamb modes at a plate edge by using orthogonality relation; pp. 283–291

(Full article in PDF format) doi: 10.3176/eng.2013.4.03


Authors

Madis Ratassepp, Aleksander Klauson, Farid Chati, Fernand Léon, Gerard Maze

Abstract

Lamb modes are widely used for non-destructive evaluation of plate-like structures and simple interpretation procedures for the analysis of the monitored structures are needed. In this study we apply the orthogonality relation based method for post-processing Finite Element (FE) predictions in order to separate Lamb modes at a plate edge. The reflected wave field from the free edge is a superposition of all the eigenmodes of an infinite plate. The eigenmode amplitudes of the reflected wave field are determined by applying the orthogonality-based method. Overlapping wavepackets of Lamb modes at a plate edge are simulated by using the FE model of the incident S0 mode in a plate with a crack. Time-domain signals of propagating and non-propagating modes are extracted.

Keywords

Lamb modes, orthogonality, mode separation.

References

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Current Issue: Vol. 19, Issue 4, 2013





Publishing schedule:
No. 1: 20 March
No. 2: 20 June
No. 3: 20 September
No. 4: 20 December