Spiral Creeping Waves in Ultrasonic Angled-Beam Shear Wave Inspection of Fastener Holes in Multilayer Structures

摘要

This paper explores the propagation and scattering of spiral creeping waves around a fastener hole. Preliminary experimental data demonstrates the presence of spiral creeping waves in angled beam inspection and the benefit for detecting cracks of varying angular location. Analytical models are used to provide insight into the propagation and focusing of spiral creeping waves around cylindrical holes. A hybrid numerical method is proposed as a measurement model for 3D scattering from holes with cracks.