The reflection of guided waves from circumferential notches in pipes

The reflection of the L(0,2), axially symmetric guided elastic wave from notches in pipes is examined, using laboratory experiments and finite element simulations. The results show that the reflection coefficient of this mode is very close to a linear function of the circumferential extent of the notch, and is a stronger function of the through thickness depth of the notch. The motivation for the work was the development of a technique for inspecting chemical plant pipework, but the study addresses the nature of the reflection function and has general applicability.