Ice Resistance Tests on Two Models of the WTGB Icebreaker
For the particular full-scale conditions modelled in the tests, the dimensionless level ice resistance obtained with the two models of the 140-foot WTGB was essentially independent of the model scale. The fact that no scale effects were identified in the present tests can be interpreted in two ways:...
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ftdtic:ADP003820 2023-05-15T16:41:21+02:00 Ice Resistance Tests on Two Models of the WTGB Icebreaker Tatinclaux,J. C. Humphreys,D. H. COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH 1983-08 text/html http://www.dtic.mil/docs/citations/ADP003820 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADP003820 en eng http://www.dtic.mil/docs/citations/ADP003820 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS *ICE *MODEL TESTS *SHIP MODELS RESISTANCE ICEBREAKERS TUGBOATS SHIP MOTION MECHANICAL PROPERTIES SCALING FACTOR HEAVING PITCH(MOTION) MATHEMATICAL ANALYSIS WTGB class vessels Ice resistance Cauchy number Froude number Component Reports Text 1983 ftdtic 2016-02-21T19:55:56Z For the particular full-scale conditions modelled in the tests, the dimensionless level ice resistance obtained with the two models of the 140-foot WTGB was essentially independent of the model scale. The fact that no scale effects were identified in the present tests can be interpreted in two ways: one is that icebreakers of size and operating conditions in ice similar to those of the WTGB can be confidently model tested at a scale of at least 1:24. The second interpretation is that model tests of icebreakers may be conducted in model ice 2 cm thick or thicker and/or with a bending strength of 30 kPa or more, since these values were the test conditions for the smaller WTGB model; these tests conditions would then specify a limiting model scale so that they correspond to the desired operating conditions of an icebreaker under design. By conducting model tests not only in level ice but also through broken ice channels, it was possible to separate the level ice resistance into two main components. According to this analysis, it was shown that the ice-breaking component is primarily a function of the Cauchy number but also the Froude number, especially at speed low enough for the ship to experience significant pitching and heaving motions when riding on the level ice and falling back as the ice sheet fails. This article is from 'Proceedings of the General Meeting of the American Towing Tank Conference (20th) Held at Hoboken, New Jersey on 2-4 August 1983. Volume 2,' AD-A144 227. p627-638. Text Ice Sheet Icebreaker Defense Technical Information Center: DTIC Technical Reports database |
institution |
Open Polar |
collection |
Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
*ICE *MODEL TESTS *SHIP MODELS RESISTANCE ICEBREAKERS TUGBOATS SHIP MOTION MECHANICAL PROPERTIES SCALING FACTOR HEAVING PITCH(MOTION) MATHEMATICAL ANALYSIS WTGB class vessels Ice resistance Cauchy number Froude number Component Reports |
spellingShingle |
*ICE *MODEL TESTS *SHIP MODELS RESISTANCE ICEBREAKERS TUGBOATS SHIP MOTION MECHANICAL PROPERTIES SCALING FACTOR HEAVING PITCH(MOTION) MATHEMATICAL ANALYSIS WTGB class vessels Ice resistance Cauchy number Froude number Component Reports Tatinclaux,J. C. Humphreys,D. H. Ice Resistance Tests on Two Models of the WTGB Icebreaker |
topic_facet |
*ICE *MODEL TESTS *SHIP MODELS RESISTANCE ICEBREAKERS TUGBOATS SHIP MOTION MECHANICAL PROPERTIES SCALING FACTOR HEAVING PITCH(MOTION) MATHEMATICAL ANALYSIS WTGB class vessels Ice resistance Cauchy number Froude number Component Reports |
description |
For the particular full-scale conditions modelled in the tests, the dimensionless level ice resistance obtained with the two models of the 140-foot WTGB was essentially independent of the model scale. The fact that no scale effects were identified in the present tests can be interpreted in two ways: one is that icebreakers of size and operating conditions in ice similar to those of the WTGB can be confidently model tested at a scale of at least 1:24. The second interpretation is that model tests of icebreakers may be conducted in model ice 2 cm thick or thicker and/or with a bending strength of 30 kPa or more, since these values were the test conditions for the smaller WTGB model; these tests conditions would then specify a limiting model scale so that they correspond to the desired operating conditions of an icebreaker under design. By conducting model tests not only in level ice but also through broken ice channels, it was possible to separate the level ice resistance into two main components. According to this analysis, it was shown that the ice-breaking component is primarily a function of the Cauchy number but also the Froude number, especially at speed low enough for the ship to experience significant pitching and heaving motions when riding on the level ice and falling back as the ice sheet fails. This article is from 'Proceedings of the General Meeting of the American Towing Tank Conference (20th) Held at Hoboken, New Jersey on 2-4 August 1983. Volume 2,' AD-A144 227. p627-638. |
author2 |
COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH |
format |
Text |
author |
Tatinclaux,J. C. Humphreys,D. H. |
author_facet |
Tatinclaux,J. C. Humphreys,D. H. |
author_sort |
Tatinclaux,J. C. |
title |
Ice Resistance Tests on Two Models of the WTGB Icebreaker |
title_short |
Ice Resistance Tests on Two Models of the WTGB Icebreaker |
title_full |
Ice Resistance Tests on Two Models of the WTGB Icebreaker |
title_fullStr |
Ice Resistance Tests on Two Models of the WTGB Icebreaker |
title_full_unstemmed |
Ice Resistance Tests on Two Models of the WTGB Icebreaker |
title_sort |
ice resistance tests on two models of the wtgb icebreaker |
publishDate |
1983 |
url |
http://www.dtic.mil/docs/citations/ADP003820 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADP003820 |
genre |
Ice Sheet Icebreaker |
genre_facet |
Ice Sheet Icebreaker |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADP003820 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766031783904673792 |