Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy.
When low frequency underwater sound interacts with the Arctic ice cover, not only will it be reflected from the plane and scattered in all directions from roughness elements, but it will also be diffracted at leads and reradiated from flexural waves in the ice. These phenomena have been studied in a...
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ftdtic:ADA176654 2023-05-15T14:39:36+02:00 Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. Denny,Patrick L. Johnson,Kevin R. NAVAL POSTGRADUATE SCHOOL MONTEREY CA 1986-12 text/html http://www.dtic.mil/docs/citations/ADA176654 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA176654 en eng http://www.dtic.mil/docs/citations/ADA176654 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Snow Ice and Permafrost Acoustics *ACOUSTIC SCATTERING *SEA ICE VELOCITY SOURCES CONTRAST MATERIALS THESES ACRYLIC RESINS BACKSCATTERING REFLECTION TRANSMITTANCE ICE PULSES COEFFICIENTS STRENGTH(GENERAL) PRESSURE COVERINGS UNDERWATER ACOUSTICS ROUGHNESS FLEXURAL PROPERTIES LOW FREQUENCY UNDERWATER SOUND WAVES UNDERWATER ACOUSTIC IMPEDANCE ARCTIC REGIONS RIDGES ACOUSTIC COATINGS UNDERICE Text 1986 ftdtic 2016-02-21T02:58:03Z When low frequency underwater sound interacts with the Arctic ice cover, not only will it be reflected from the plane and scattered in all directions from roughness elements, but it will also be diffracted at leads and reradiated from flexural waves in the ice. These phenomena have been studied in an anechoic tank by pulse transmission from an underwater point source to a series of large floating acrylic plate models, each representing a different type of ice cover. The flexural wave speed, the plate and lead dimensions and the acoustic roughness are accurately scaled, and the specific acoustic impedance contrast is approximately modeled by the selection of the acrylic material. The physical contributors to the gross reflection coefficient and backscattering strength are identified and compared for models of a plane ice layer, an Arctic ice pressure ridge, edges of leads, and a rubble field of ice. Keywords: Underwater Acoustics; Scatter, Backscatter; Arctic Ice; Reflection Coefficient; Flexural Waves; Theses. Text Arctic Ice permafrost Sea ice Defense Technical Information Center: DTIC Technical Reports database Arctic |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Snow Ice and Permafrost Acoustics *ACOUSTIC SCATTERING *SEA ICE VELOCITY SOURCES CONTRAST MATERIALS THESES ACRYLIC RESINS BACKSCATTERING REFLECTION TRANSMITTANCE ICE PULSES COEFFICIENTS STRENGTH(GENERAL) PRESSURE COVERINGS UNDERWATER ACOUSTICS ROUGHNESS FLEXURAL PROPERTIES LOW FREQUENCY UNDERWATER SOUND WAVES UNDERWATER ACOUSTIC IMPEDANCE ARCTIC REGIONS RIDGES ACOUSTIC COATINGS UNDERICE |
spellingShingle |
Snow Ice and Permafrost Acoustics *ACOUSTIC SCATTERING *SEA ICE VELOCITY SOURCES CONTRAST MATERIALS THESES ACRYLIC RESINS BACKSCATTERING REFLECTION TRANSMITTANCE ICE PULSES COEFFICIENTS STRENGTH(GENERAL) PRESSURE COVERINGS UNDERWATER ACOUSTICS ROUGHNESS FLEXURAL PROPERTIES LOW FREQUENCY UNDERWATER SOUND WAVES UNDERWATER ACOUSTIC IMPEDANCE ARCTIC REGIONS RIDGES ACOUSTIC COATINGS UNDERICE Denny,Patrick L. Johnson,Kevin R. Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
topic_facet |
Snow Ice and Permafrost Acoustics *ACOUSTIC SCATTERING *SEA ICE VELOCITY SOURCES CONTRAST MATERIALS THESES ACRYLIC RESINS BACKSCATTERING REFLECTION TRANSMITTANCE ICE PULSES COEFFICIENTS STRENGTH(GENERAL) PRESSURE COVERINGS UNDERWATER ACOUSTICS ROUGHNESS FLEXURAL PROPERTIES LOW FREQUENCY UNDERWATER SOUND WAVES UNDERWATER ACOUSTIC IMPEDANCE ARCTIC REGIONS RIDGES ACOUSTIC COATINGS UNDERICE |
description |
When low frequency underwater sound interacts with the Arctic ice cover, not only will it be reflected from the plane and scattered in all directions from roughness elements, but it will also be diffracted at leads and reradiated from flexural waves in the ice. These phenomena have been studied in an anechoic tank by pulse transmission from an underwater point source to a series of large floating acrylic plate models, each representing a different type of ice cover. The flexural wave speed, the plate and lead dimensions and the acoustic roughness are accurately scaled, and the specific acoustic impedance contrast is approximately modeled by the selection of the acrylic material. The physical contributors to the gross reflection coefficient and backscattering strength are identified and compared for models of a plane ice layer, an Arctic ice pressure ridge, edges of leads, and a rubble field of ice. Keywords: Underwater Acoustics; Scatter, Backscatter; Arctic Ice; Reflection Coefficient; Flexural Waves; Theses. |
author2 |
NAVAL POSTGRADUATE SCHOOL MONTEREY CA |
format |
Text |
author |
Denny,Patrick L. Johnson,Kevin R. |
author_facet |
Denny,Patrick L. Johnson,Kevin R. |
author_sort |
Denny,Patrick L. |
title |
Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
title_short |
Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
title_full |
Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
title_fullStr |
Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
title_full_unstemmed |
Underwater Acoustic Scatter from a Model of the Arctic Ice Canopy. |
title_sort |
underwater acoustic scatter from a model of the arctic ice canopy. |
publishDate |
1986 |
url |
http://www.dtic.mil/docs/citations/ADA176654 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA176654 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Ice permafrost Sea ice |
genre_facet |
Arctic Ice permafrost Sea ice |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA176654 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766311580654370816 |