Time-Domain First Born Approximations to Elastodynamic Backscatter with Applications to Non-Destructive Evaluation of Composites.
Abstract
The first Born approximations to solutions of a time-domain integral equation were used to obtain the backscattered dilatation wave response from spherical and cylindrical inclusions of arbitrary homogeneous anisotropic elastic material embedded within a homogeneous isotropic host. For large ka, where the validity of the first Born approximation is questioned, the time waveform responses from cylinders and spheres are markedly different; for ka approaches limit of 0, they have identical time form with amplitudes dependent upon the volume of the scatterer. Excellent agreement with an experimental result for scattering from a cylindrical void was obtained for a value of ka = 0.32. A 'transparency condition' was obtained, allowing that for certain combinations of both density and stiffness of the scatterer and host, the scatterer appears transparent to the incoming wave in the first Born approximation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1981
- Accession Number
- ADA115566
Entities
People
- Gregory T. Warhola
Organizations
- Air Force Institute of Technology