Accession Number:

ADA231122

Title:

Scattering in the Time Domain from Submerged Elastic Shells at Coincidence Frequencies

Descriptive Note:

Proceedings rept.

Corporate Author:

NAVAL OCEANOGRAPHIC AND ATMOSPHERIC RESEARCH LAB STENNIS SPACE CENTER MS

Personal Author(s):

Report Date:

1990-01-01

Pagination or Media Count:

5.0

Abstract:

It is known that when scattering from elastic shells, a large resonance is produced at frequencies corresponding to values in which the flexural phase velocity is roughly equal to the speed of sound in the fluid. A systematic analysis indicates that the large response is due mainly to water born waves labeled A waves which have narrow half-widths and manifest themselves as pronounces spikes in the form function as well as weaker flexural resonances labeled AO which have rather larger half-widths and produce an envelop effect due to overlapping resonances over a broad frequency range. These results are analyzed within the context of a new time domain resonance scattering theory and are shown to produce characteristic transient return signals. From these signals it is possible to calculate both the half-width of the A waves as well as their group velocities.

Subject Categories:

  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE