Drifting rogue packets
Modulation instability (MI) is one possible mechanism to explain the formation of extreme waves in uni-directional and narrow-banded seas. It can be triggered, when side-bands around the main frequency are excited and subsequently follow an exponential growth. In physical domain this dynamics transl...
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fttuhamburg:oai:tore.tuhh.de:11420/2581 2023-08-20T04:02:42+02:00 Drifting rogue packets Chabchoub, Amin Hoffmann, Norbert Akhmediev, Nail N. Waseda, Takuji 2018-09-25 http://hdl.handle.net/11420/2581 en eng Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2018 978-079185122-7 International Conference on Offshore Mechanics and Arctic Engineering (OMAE 2018) http://hdl.handle.net/11420/2581 2-s2.0-85055585024 Conference Paper Other 2018 fttuhamburg 2023-07-28T09:22:43Z Modulation instability (MI) is one possible mechanism to explain the formation of extreme waves in uni-directional and narrow-banded seas. It can be triggered, when side-bands around the main frequency are excited and subsequently follow an exponential growth. In physical domain this dynamics translates to periodic pulsations of wave groups that can reach heights up to three times the initial amplitude of the wave train. It is well-known that these periodic wave groups propagate with approximately half the waves phase speed in deep-water. We report an experimental study on modulationally unstable wave groups that propagate with a velocity that is higher than the group velocity since the modulation frequency is complex. It is shown that when this additional velocity to the wave groups is small a good agreement with exact nonlinear Schrödinger (NLS) models, that describe the nonlinear stage of MI, is reached. Otherwise a significant deviation is observed that could be compensated when increasing accuracy of the water wave modeling beyond NLS. Conference Object Arctic TUHH Open Research (TORE - Technische Universität Hamburg) Volume 3: Structures, Safety, and Reliability |
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Open Polar |
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TUHH Open Research (TORE - Technische Universität Hamburg) |
op_collection_id |
fttuhamburg |
language |
English |
description |
Modulation instability (MI) is one possible mechanism to explain the formation of extreme waves in uni-directional and narrow-banded seas. It can be triggered, when side-bands around the main frequency are excited and subsequently follow an exponential growth. In physical domain this dynamics translates to periodic pulsations of wave groups that can reach heights up to three times the initial amplitude of the wave train. It is well-known that these periodic wave groups propagate with approximately half the waves phase speed in deep-water. We report an experimental study on modulationally unstable wave groups that propagate with a velocity that is higher than the group velocity since the modulation frequency is complex. It is shown that when this additional velocity to the wave groups is small a good agreement with exact nonlinear Schrödinger (NLS) models, that describe the nonlinear stage of MI, is reached. Otherwise a significant deviation is observed that could be compensated when increasing accuracy of the water wave modeling beyond NLS. |
format |
Conference Object |
author |
Chabchoub, Amin Hoffmann, Norbert Akhmediev, Nail N. Waseda, Takuji |
spellingShingle |
Chabchoub, Amin Hoffmann, Norbert Akhmediev, Nail N. Waseda, Takuji Drifting rogue packets |
author_facet |
Chabchoub, Amin Hoffmann, Norbert Akhmediev, Nail N. Waseda, Takuji |
author_sort |
Chabchoub, Amin |
title |
Drifting rogue packets |
title_short |
Drifting rogue packets |
title_full |
Drifting rogue packets |
title_fullStr |
Drifting rogue packets |
title_full_unstemmed |
Drifting rogue packets |
title_sort |
drifting rogue packets |
publishDate |
2018 |
url |
http://hdl.handle.net/11420/2581 |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2018 978-079185122-7 International Conference on Offshore Mechanics and Arctic Engineering (OMAE 2018) http://hdl.handle.net/11420/2581 2-s2.0-85055585024 |
container_title |
Volume 3: Structures, Safety, and Reliability |
_version_ |
1774713294158823424 |