TITLE

Finite-difference modelling of pulse-echo scattering using a water-coupled transducer

AUTHOR(S)
Stacey, Richard
PUB. DATE
May 2000
SOURCE
AIP Conference Proceedings;2000, Vol. 509 Issue 1, p113
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We report the development of new techniques for modeling pulse-echo scattering using a water-coupled transducer, and their success in accurately predicting both the size and shape of the echoes from small solid defects. Our new methods use separate grids to model the solid and the liquid, and these are only related along the interface using pseudonode formulations based on the boundary conditions. The twin grid formulation does not have any problems with discontinuities along the interface. It has also been shown to have excellent stability properties. When we compare our finite difference predictions with experimental data from known defects, we take care to subtract measurements made without the defect (with all else unchanged) from the measurements with the defect, in order to avoid spurious interface echoes. We do this for both the experimental and the finite-difference “data.” The finite difference predictions match the experimental measurements to high accuracy. Having validated the finite difference techniques, we can use them to monitor and visualize the various scattered and reflected waves, giving valuable insights into their physical origins. © 2000 American Institute of Physics.
ACCESSION #
6029280

 

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