Forward Sound Propagation Around Seamounts

Forward Sound Propagation Around Seamounts
Author:
Publisher:
Total Pages:
Release: 2006
Genre:
ISBN:

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2009.

Sound Propagation Around Underwater Seamounts

Sound Propagation Around Underwater Seamounts
Author: Joseph J. Sikora (III.)
Publisher:
Total Pages: 242
Release: 2005
Genre: Seamounts
ISBN:

This thesis develops and utilizes a method for analyzing data from the North Pacific Acoustic Laboratory's (NPAL) Basin Acoustic Seamount Scattering Experiment (BASSEX). BASSEX was designed to provide data to support the development of analytical techniques and methods which improve the understanding of sound propagation around underwater seamounts. The depth-dependent sound velocity profile of typical ocean waveguides force sound to travel in convergence zones about a minimum sound speed depth. This ducted nature of the ocean makes modeling the acoustic field around seamounts particularly challenging, compared to an isovelocity medium. The conical shape of seamounts also adds to the complexity of the scatter field. It is important to the U.S. Navy to understand how sound is diffracted around this type of topographic feature. Underwater seamounts can be used to conceal submarines by absorbing and scattering the sound they emit. BASSEX measurements have characterized the size and shape of the forward scatter field around the Kermit-Roosevelt Seamount in the Pacific Ocean. Kermit-Roosevelt is a large, conical seamount which shoals close to the minimum sound speed depth, making it ideal for study. Acoustic sources, including M-sequence and linear frequency-modulated sources, were stationed around the seamount at megameter ranges. A hydrophone array was towed around the seamount to locations which allowed measurement of the perturbation zone. Results from the method developed in this thesis show that the size and shape of the perturbation zone measured coincides with theoretical and experimental results derived in previous work.

Progress in Underwater Acoustics

Progress in Underwater Acoustics
Author: Harold Merklinger
Publisher: Springer Science & Business Media
Total Pages: 815
Release: 2012-12-06
Genre: Science
ISBN: 1461318718

IMAGE TRACKS AT HALIFAX by L.B. Felsen All living kind much effort spend Some model modes, some model rays, To cope with their environment Some feel that spectra all portrays. Some use their eyes, some use their nose Then there are those who with despatch, To sense where other things repose. Take refuge in the ocean wedge. For one group, nothing's more profound Than to explore the world with sound. If things get messy, randomize. These audio diagnosticians What's partly smooth, determinize. You ponder, is it this or that? Go by the name of acousticians. And wish you were a lowly bat They regularly meet to check Whether their sonogram's on track. The meeting's hosts did treat us well. With images stored in their packs, They let the climate cast its spell. This year they came to Halifax. No weath'ry hope was placed in vain. There they combined with ocean types We were exposed to wind and rain, And each could hear the other's gripes. We glimpsed blue sky through clouds dispersed. A meeting naturally does start But rainy sequence was reversed: Reviewing present state of art. The ocean types would like it wet What we found out is where it's at: Yet they got stuck with sun instead. We cannot hope to match the bat Each confrence has the same refrain: Computer printouts by the reams It has been fun to meet again.

Sound Propagation Around Underwater Seamounts

Sound Propagation Around Underwater Seamounts
Author:
Publisher:
Total Pages:
Release: 2005
Genre:
ISBN:

Submitted in partial fulfillment of the requirements for Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2005.

12th IMACS world congress

12th IMACS world congress
Author: International Association for Mathematics and Computers in Simulation
Publisher:
Total Pages: 788
Release: 1988
Genre: Algorithms
ISBN:

Modeling of Sound Propagation in the Sea

Modeling of Sound Propagation in the Sea
Author: A. N. Barkhatov
Publisher: Springer
Total Pages: 91
Release: 2013-05-14
Genre: Technology & Engineering
ISBN: 9781468415834

The book is concerned with the application of modeling techniques and procedures to the investigation of sound propagation in the sea. The modeling method affords a means for studying the laws governing the sound fields in the sea and in other, similar media under controlled laboratory conditions and can be used in underwater acoustics as a coroHary to field experiments. The method has a number of advantages, principal of which are the relative simplicity and low cost of model tests by com parison with fuH-scale tests under oceanic conditions, the high accuracy of acoustical mea surements, excellent reproducibility of the measurement results, and the capability of rapidly varying the experimental conditions, which, unlike the conditions of field experiments, are under complete control. For the modeling of sound propagation in the sea the latter is treated, depending on the problem to be solved, either as a volume-homogeneous medium or as a medium possessing regular and randomly-distributed inhomogeneities. We direct our primary attention in the book to the modeling of layered-inhomogeneous media, but we also discuss separate problems bearing on the study of sound propagation in the sea. It is demonstrated in examples how modeling is employed to investigate the sound field in the ocean for certain typical vertical distributions of the velocity of sound in the ocean.

Marine Acoustics

Marine Acoustics
Author: James L. Buchanan
Publisher: SIAM
Total Pages: 344
Release: 2004-01-01
Genre: Science
ISBN: 0898715474

Marine Acoustics: Direct and Inverse Problems presents current research trends in the field of underwater acoustic wave direct and inverse problems. It is the first to investigate inverse problems in an ocean environment, with heavy emphasis on the description and resolution of the forward scattering problem.