Scattering of Lamb waves from edge cracks in circular holes for understanding damage detection in more complex structures

Engineering structures such as aircraft do consist of millions of rivets and thus holes in their structure from where most likely cracks generate once the structures age. Although riveted structures may seem comparatively simple, understanding the way guided waves propagate through structures is far from being well understood. A way on how to gain this understanding may be achieved by initially fully understanding the propagation of guided waves in the simplest type of component before gradually moving up to structures of higher complexity. In the case of riveted joints this simpler type of structure is possibly a plate with a hole. In order to ease the interpretation of damage detection results, the understanding of the physical phenomena behind Lamb wave propagation has to be enhanced. Since small cracks are initiated at rivet holes, initially understanding the elastic wave incidence from edge cracks at open holes becomes a necessity.