Resonant phenomena of circumferential SH waves converted from T(0,1) mode guided waves at non-axisymmetric defects

In this paper, propagation behaviors of the T(0,1) mode guided waves at non-axisymmetric defects were considered with the FEM simulations, the theory and the experimental results. It was found that resonances of circumferential (C-) SH waves converted from the T(0,1) mode guided waves at non-axisymmetric defects occurred clearly at the specific frequencies estimated by the theory. The standing waves of the C-SH waves were verified experimentally with the laser vibrometer for detecting the distributions of the particle displacement speed along the girth. The FEM simulations were also underpinned the phenomena. The resonances were confirmed obviously on condition that the C-SH waves formed standing waves along the girth. Conversely, the resonances were not confirmed on condition that the other C-guided wave, namely the C-Lamb waves, formed the standing waves. In addition, the other T(0,1) mode guided waves that were originated from the resonant C-SH waves were confirmed while the resonances occurred.