Vortex-induced motion of a free-standing riser below the critical mass ratio
The presented work studied the vortex-induced motion (VIM) response of a free-standing riser (FSR) with varied riser length and buoyancy can (BC) mass with an ultimate aim to find a combination that would reduce the motion of the system. Specifically, four model configurations were experimentally te...
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Online Access: | https://doi.org/10.1115/OMAE2017-61399 http://ecite.utas.edu.au/124327 |
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ftunivtasecite:oai:ecite.utas.edu.au:124327 2023-05-15T14:26:20+02:00 Vortex-induced motion of a free-standing riser below the critical mass ratio Florager, C Balash, C 2017 https://doi.org/10.1115/OMAE2017-61399 http://ecite.utas.edu.au/124327 en eng American Society of Mechanical Engineers http://dx.doi.org/10.1115/OMAE2017-61399 Florager, C and Balash, C, Vortex-induced motion of a free-standing riser below the critical mass ratio, Proceedings of the ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering, 25-30 June 2017, Trondheim, Norway, pp. V002T08A032-039. ISBN 978-0-7918-5764-9 (2017) [Refereed Conference Paper] http://ecite.utas.edu.au/124327 Engineering Maritime Engineering Ship and Platform Structures Refereed Conference Paper PeerReviewed 2017 ftunivtasecite https://doi.org/10.1115/OMAE2017-61399 2019-12-13T22:23:01Z The presented work studied the vortex-induced motion (VIM) response of a free-standing riser (FSR) with varied riser length and buoyancy can (BC) mass with an ultimate aim to find a combination that would reduce the motion of the system. Specifically, four model configurations were experimentally tested in a flume tank over a range of flow velocities, with the BC motion recorded by a submersible camera positioned directly above the model; consequently, inline (IL) and crossflow (CF) amplitudes were estimated with a motion tracking software. In the pre-resonant flow regime, non-dimensionally, minimal differences were observed between the CF amplitudes, and the IL motion was reduced with a longer riser. Given the extreme length of full-scale FSRs and inherent low natural frequency, it is impractical to increase the riser tension to a point where VIM would not occur under normal environmental conditions. Alternatively, increasing the mass ratio of the BC so that it is above the critical mass ratio of 0.54 (the ratio of the mass of the body to the mass of the fluid) would limit the resonant flow velocities to a finite range, but a larger BC may not be an economically viable solution, and because of the increased diameter, it would experience a larger CF amplitude during resonance. Further study into the prevention of VIM of an FSR by varying the riser length and BC mass is unlikely to be beneficial. Conference Object Arctic eCite UTAS (University of Tasmania) Volume 2: Prof. Carl Martin Larsen and Dr. Owen Oakley Honoring Symposia on CFD and VIV |
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eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Engineering Maritime Engineering Ship and Platform Structures |
spellingShingle |
Engineering Maritime Engineering Ship and Platform Structures Florager, C Balash, C Vortex-induced motion of a free-standing riser below the critical mass ratio |
topic_facet |
Engineering Maritime Engineering Ship and Platform Structures |
description |
The presented work studied the vortex-induced motion (VIM) response of a free-standing riser (FSR) with varied riser length and buoyancy can (BC) mass with an ultimate aim to find a combination that would reduce the motion of the system. Specifically, four model configurations were experimentally tested in a flume tank over a range of flow velocities, with the BC motion recorded by a submersible camera positioned directly above the model; consequently, inline (IL) and crossflow (CF) amplitudes were estimated with a motion tracking software. In the pre-resonant flow regime, non-dimensionally, minimal differences were observed between the CF amplitudes, and the IL motion was reduced with a longer riser. Given the extreme length of full-scale FSRs and inherent low natural frequency, it is impractical to increase the riser tension to a point where VIM would not occur under normal environmental conditions. Alternatively, increasing the mass ratio of the BC so that it is above the critical mass ratio of 0.54 (the ratio of the mass of the body to the mass of the fluid) would limit the resonant flow velocities to a finite range, but a larger BC may not be an economically viable solution, and because of the increased diameter, it would experience a larger CF amplitude during resonance. Further study into the prevention of VIM of an FSR by varying the riser length and BC mass is unlikely to be beneficial. |
format |
Conference Object |
author |
Florager, C Balash, C |
author_facet |
Florager, C Balash, C |
author_sort |
Florager, C |
title |
Vortex-induced motion of a free-standing riser below the critical mass ratio |
title_short |
Vortex-induced motion of a free-standing riser below the critical mass ratio |
title_full |
Vortex-induced motion of a free-standing riser below the critical mass ratio |
title_fullStr |
Vortex-induced motion of a free-standing riser below the critical mass ratio |
title_full_unstemmed |
Vortex-induced motion of a free-standing riser below the critical mass ratio |
title_sort |
vortex-induced motion of a free-standing riser below the critical mass ratio |
publisher |
American Society of Mechanical Engineers |
publishDate |
2017 |
url |
https://doi.org/10.1115/OMAE2017-61399 http://ecite.utas.edu.au/124327 |
genre |
Arctic |
genre_facet |
Arctic |
op_relation |
http://dx.doi.org/10.1115/OMAE2017-61399 Florager, C and Balash, C, Vortex-induced motion of a free-standing riser below the critical mass ratio, Proceedings of the ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering, 25-30 June 2017, Trondheim, Norway, pp. V002T08A032-039. ISBN 978-0-7918-5764-9 (2017) [Refereed Conference Paper] http://ecite.utas.edu.au/124327 |
op_doi |
https://doi.org/10.1115/OMAE2017-61399 |
container_title |
Volume 2: Prof. Carl Martin Larsen and Dr. Owen Oakley Honoring Symposia on CFD and VIV |
_version_ |
1766298848981942272 |