Sea Ice Mechanics Research Progress.
The architecture for a new large scale (5 to 100 km, 1 hour to 1 day) sea ice dynamics model based on an anisotropic constitutive law is presented here. This architecture accounts directly for refrozen lead systems in the pack ice strength (with an anisotropic failure surface) and in the ice thickne...
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ftdtic:ADA327636 2023-05-15T16:37:15+02:00 Sea Ice Mechanics Research Progress. Coon, Max D. NORTHWEST RESEARCH ASSOCIATES INC BELLEVUE WA 1997-07-18 text/html http://www.dtic.mil/docs/citations/ADA327636 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA327636 en eng http://www.dtic.mil/docs/citations/ADA327636 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Snow Ice and Permafrost *ICE MECHANICS *SEA ICE SCALE MODELS DEFORMATION FRACTURE(MECHANICS) ANISOTROPY SHEAR STRESSES ELASTOPLASTICITY BUOYS ICE DYNAMICS MODELS Text 1997 ftdtic 2016-02-19T20:35:11Z The architecture for a new large scale (5 to 100 km, 1 hour to 1 day) sea ice dynamics model based on an anisotropic constitutive law is presented here. This architecture accounts directly for refrozen lead systems in the pack ice strength (with an anisotropic failure surface) and in the ice thickness distribution (with an oriented thickness distribution). The lower limit (5 km) of the model resolution is controlled by the fracture spacing of old, thicker ice and the maximum lead width. The upper limit of the model resolution (100 km) is controlled by curvature in the lead directions and variations in the lead width. These in turn are controlled by the variations in internal ice stress due to driving forces (winds and currents), which set the time resolution. This architecture features abrupt changes in the failure surface and the associated flow rule that cannot be averaged over a time step. In addition, the principal stress normal to a new lead must be zero as it opens. This model has sub-scale simulations that allow for the inclusion of phenomena such as ridging, rafting, buckling, and fracture on the behavior of the ice. With this new ice constitutive law, it is possible to directly test the ice failure strength, plastic flow rule, and ice thickness distribution. The data most useful for this testing come from ice stress and position buoys together with SAR deformation data. Some data comparisons have already been made. Text Ice permafrost Sea ice Defense Technical Information Center: DTIC Technical Reports database |
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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 *ICE MECHANICS *SEA ICE SCALE MODELS DEFORMATION FRACTURE(MECHANICS) ANISOTROPY SHEAR STRESSES ELASTOPLASTICITY BUOYS ICE DYNAMICS MODELS |
spellingShingle |
Snow Ice and Permafrost *ICE MECHANICS *SEA ICE SCALE MODELS DEFORMATION FRACTURE(MECHANICS) ANISOTROPY SHEAR STRESSES ELASTOPLASTICITY BUOYS ICE DYNAMICS MODELS Coon, Max D. Sea Ice Mechanics Research Progress. |
topic_facet |
Snow Ice and Permafrost *ICE MECHANICS *SEA ICE SCALE MODELS DEFORMATION FRACTURE(MECHANICS) ANISOTROPY SHEAR STRESSES ELASTOPLASTICITY BUOYS ICE DYNAMICS MODELS |
description |
The architecture for a new large scale (5 to 100 km, 1 hour to 1 day) sea ice dynamics model based on an anisotropic constitutive law is presented here. This architecture accounts directly for refrozen lead systems in the pack ice strength (with an anisotropic failure surface) and in the ice thickness distribution (with an oriented thickness distribution). The lower limit (5 km) of the model resolution is controlled by the fracture spacing of old, thicker ice and the maximum lead width. The upper limit of the model resolution (100 km) is controlled by curvature in the lead directions and variations in the lead width. These in turn are controlled by the variations in internal ice stress due to driving forces (winds and currents), which set the time resolution. This architecture features abrupt changes in the failure surface and the associated flow rule that cannot be averaged over a time step. In addition, the principal stress normal to a new lead must be zero as it opens. This model has sub-scale simulations that allow for the inclusion of phenomena such as ridging, rafting, buckling, and fracture on the behavior of the ice. With this new ice constitutive law, it is possible to directly test the ice failure strength, plastic flow rule, and ice thickness distribution. The data most useful for this testing come from ice stress and position buoys together with SAR deformation data. Some data comparisons have already been made. |
author2 |
NORTHWEST RESEARCH ASSOCIATES INC BELLEVUE WA |
format |
Text |
author |
Coon, Max D. |
author_facet |
Coon, Max D. |
author_sort |
Coon, Max D. |
title |
Sea Ice Mechanics Research Progress. |
title_short |
Sea Ice Mechanics Research Progress. |
title_full |
Sea Ice Mechanics Research Progress. |
title_fullStr |
Sea Ice Mechanics Research Progress. |
title_full_unstemmed |
Sea Ice Mechanics Research Progress. |
title_sort |
sea ice mechanics research progress. |
publishDate |
1997 |
url |
http://www.dtic.mil/docs/citations/ADA327636 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA327636 |
genre |
Ice permafrost Sea ice |
genre_facet |
Ice permafrost Sea ice |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA327636 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766027545380126720 |