Finite element modelling of the scattering of ultrasonic waves by isolatedflaws

A two-dimensional finite element model with absorbing boundary conditions h as been developed to investigate the scattering of ultrasonic waves in infi nite isotropic solids. The model is capable of showing a complex mode-conve rsion, when a short duration sinusoidal pulse interacts with a flaw. The em phasis is on narrow crack-like defects, cylindrical and spherical holes of size equal to the wavelength of the incident wave. The results, which are p resented in the form of snapshots and scattering cross-sections, assist in understanding wave-flaw interaction, especially mode-conversion of the inci dent field and optimizing the ultrasonic NDT. (C) 2000 Elsevier Science Ltd . All rights reserved.