Distributed Wake-Body Resonance of a Long Flexible Cylinder in Shear Flow
Author(s)
Bourguet, Rémi
Tognarelli, Michael
Beynet, Pierre
Triantafyllou, Michael S
Date Issued
July 2012
Journal
ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering
Publisher
ASME International
Citation
Bourguet, Rémi, Michael S. Triantafyllou, Michael Tognarelli, and Pierre Beynet. “Distributed Wake-Body Resonance of a Long Flexible Cylinder in Shear Flow.” ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering, 1-6 July, 2013, Rio de Janeiro, Brazil, ASME, 2013. © 2012 ASME
Version
Final published version
Abstract
The fluid-structure interaction mechanisms involved in the development of narrowband and broadband vortex-induced vibrations of long flexible structures placed in non-uniform currents are investigated by means of direct numerical simulation. We consider a tensioned beam of aspect ratio 200, free to move in both the in-line and cross-flow directions, and immersed in a sheared flow at Reynolds number 330. Both narrowband and broadband multi-frequency vibrations may develop, depending on the velocity profile of the sheared oncoming current. Narrowband vibrations occur when lock-in, i.e. the synchronization between vortex shedding and structure oscillations, is limited to a single location along the span, within the high current velocity region; thus, well-defined lock-in versus non-lock-in regions are noted along the span. In contrast, we show that broadband responses, where both high and low structural wavelengths are excited, are characterized by several isolated regions of lock-in, distributed along the length. The phenomenon of distributed lock-in impacts the synchronization of the in-line and cross-flow vibrations, and the properties of the fluid-structure energy transfer, as function of time and space. Topics: Resonance, Shear flow, Wakes, Cylinders, Locks (Waterways), Vibration, Synchronization, Cross-flow, Oscillations, Vortex-induced vibration
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1115/OMAE2012-83294
