Final Technical Report for Grant N00014-94-1-0201 (Catholic University of America).
Abstract
During this contract, research was performed to understand how acoustic radiation propagates in shallow channels using a full three-dimensional formulation that takes into account the finiteness of the characteristic correlation lengths of the index-of refraction fluctuations and surface height variations. The equations governing the modal coherence functions were derived by first developing difference equations over propagation distances that were large compared to the characteristic correlation lengths but small compared to the characteristic length during which there was significant energy transfer between modes. It was then shown under what conditions these equations could be reduced to partial differential equations that were valid for long-range propagation. Using a spectral formulation the equations were subsequently generalized to wide-angle scattering in the transverse direction. Differences between the two-dimensional and three-dimensional problems were found in a variety of cases. Numerical solutions were given to show how the energy is transferred between modes as the acoustic radiation propagates in the shallow channel.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 31, 1996
- Accession Number
- ADA313828
Entities
People
- Michael J. Beran
Organizations
- The Catholic University of America