Elastic wave energy trapping in a plate with a crack: Theory and experiment

The research aims at an experimental confirmation of the trapping mode effect that was theoretically predicted for a layered plate with a delamination. The trapping modes are eigensolutions of the related diffraction problem associated with nearly real complex points of its discrete spectrum. The effect occurs at the central frequencies coinciding with the spectral points of the integral equation to which the diffraction problem is reduced. The laser vibrometer based measurements have confirmed the trapping mode effect. The waves trapped at the delamination manifest themselves as dark spots in the snapshots of scanned surface.