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Updated: Jun 12, 2026
09:36
Characterization of Anisotropic Leaky Mode Modulators for Holovideo
Published on: March 19, 2016
Nonlinear clapping modulation of lamb modes by normally closed delamination
Gennady Shkerdin1, Christ Glorieux
1Laboratorium voor Akoestiek en Thermische Fysica, Departement Natuurkunde, Katholieke Universiteit Leuven, Leuven, Belgium. christ.glorieux@fys.kuleuven.be
Summary
This study models nonlinear Lamb wave interactions in bilayers. It predicts spectral enrichment and surface displacement changes, offering a guide for nondestructive testing of composite materials.
Area of Science:
- Solid Mechanics
- Materials Science
- Acoustics
Background:
- Nonlinear acoustic phenomena are crucial for advanced material characterization.
- Lamb waves are effective for inspecting thin structures like bilayers.
- Delaminations in composite bilayers can compromise structural integrity.
Purpose of the Study:
- To model the nonlinear interaction of probing and pump Lamb waves in a delaminated bilayer.
- To establish a criterion for delamination opening based on dynamic stress.
- To investigate the impact of nonlinear effects on surface displacement for nondestructive testing applications.
Main Methods:
- A quasi-stationary approach is employed to model the wave interaction.
- The delamination opening criterion is based on pump-wave-induced normal stress.
- Temporal evolution of contact conditions and spectral enrichment are calculated.
Main Results:
- The study predicts spectral enrichment due to cross-modulation between probing and pump waves.
- The impact of cross-modulation on surface displacement is analyzed for different probing waves.
- The influence of contact quality modulation on the observed phenomena is investigated.
Conclusions:
- The findings provide a parametric guide for using nonlinear harmonic generation of Lamb waves.
- This technique shows promise for nondestructive testing of rubber-steel composite bilayers.
- The research aids in assessing the integrity of structures like storage tanks and pipelines.
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