Propagation of Lamb waves in a plate with a periodic grating: Interpretation by phonon

Abstract

In this paper the propagation of Lamb waves in an aluminium plate with a periodic grating containing triangular grooves is studied. Numerical simulations (FEM) are performed. A single incident mode is excited on a flat area and the interaction with the periodic grating is studied. Reflected converted waves are observed when the incident Lamb wave passes through the grating. At the entrance of the periodic grating, a phonon relation is written between the incident signal, the converted mode, and the phonon related to the grating. An experimental verification of the phonon relation is carried out.