The high-frequency description of scatter of a plane compressional wave by an elliptic crack.
High-frequency approximations that can be interpreted in terms of the Uniform Geometrical Theory of Diffraction (UGTD) and Uniform Kirchhoff Approximation (UKA) are used to develop a code for modeling ultrasonic scatter of a plane compressional wave by an elliptic crack in the radiating near field. The approximations are intercompared and partially validated against a direct numerical code based on an FD (Finite-Difference) scheme. At present, in many realistic situations the approximate codes of the type described here offer the only viable simulation tool; purely numeric codes are not only much slower, they still require too much computer memory to simulate the complex structure of the radiating near fields.
Fradkin
L Ju
LJ
Waves and Fields Research Group, ECCE, FESBE, London South Bank University, London SE1 0AA, England, United Kingdom. fradkil@lsbu.ac.uk
Stacey
R
R
D008962:Models, Theoretical; D014465:Ultrasonics