Mechanics of nonlinear short-wave generation by a moored near-surface buoy
We consider the nonlinear interaction problem of surface waves with a tethered near-surface buoy. Our objective is to investigate mechanisms for nonlinear short surface wave generation in this complete coupled wave-buoy-cable dynamical system. We develop an effective numerical simulation capabili...
| Main Authors: | , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
Cambridge University Press
2005
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/1721.1/25617 |
| _version_ | 1826203622596149248 |
|---|---|
| author | Zhu, Q. Liu, Y. Tjavaras, A.A. Triantafyllou, M.S. Yue, D.K.P. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Zhu, Q. Liu, Y. Tjavaras, A.A. Triantafyllou, M.S. Yue, D.K.P. |
| author_sort | Zhu, Q. |
| collection | MIT |
| description | We consider the nonlinear interaction problem of surface waves with a tethered
near-surface buoy. Our objective is to investigate mechanisms for nonlinear short
surface wave generation in this complete coupled wave-buoy-cable dynamical system.
We develop an effective numerical simulation capability coupling an efficient and
high-resolution high-order spectral method for the nonlinear wave-buoy interaction
problem with a robust implicit finite-difference method for the cable-buoy dynamics.
The numerical scheme accounts for nonlinear wave-wave and wave-body interactions
up to an arbitrary high order in the wave steepness and is able to treat extreme motions
of the cable including conditions of negative cable tension. Systematic simulations
show that beyond a small threshold value of the incident wave amplitude, the buoy
performs chaotic motions, characterized by the snapping of the cable. The root
cause of the chaotic response is the interplay between the snapping of the cable
and the generation of surface waves, which provides a source of strong (radiation)
damping. As a result of this interaction, the chaotic buoy motion switches between
two competing modes of snapping response: one with larger average peak amplitude
and lower characteristic frequency, and the other with smaller amplitude and higher
frequency. The generated high-harmonic/short surface waves are greatly amplified
once the chaotic motion sets in. Analyses of the radiated wave spectra show significant
energy at higher frequencies which is orders of magnitude larger than can be expected
from nonlinear generation under regular motion. |
| first_indexed | 2024-09-23T12:40:12Z |
| format | Article |
| id | mit-1721.1/25617 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2025-02-19T04:21:41Z |
| publishDate | 2005 |
| publisher | Cambridge University Press |
| record_format | dspace |
| spelling | mit-1721.1/256172025-02-11T19:45:55Z Mechanics of nonlinear short-wave generation by a moored near-surface buoy Zhu, Q. Liu, Y. Tjavaras, A.A. Triantafyllou, M.S. Yue, D.K.P. Massachusetts Institute of Technology. Department of Mechanical Engineering surface buoy nonlinear short-wave numerical simulation We consider the nonlinear interaction problem of surface waves with a tethered near-surface buoy. Our objective is to investigate mechanisms for nonlinear short surface wave generation in this complete coupled wave-buoy-cable dynamical system. We develop an effective numerical simulation capability coupling an efficient and high-resolution high-order spectral method for the nonlinear wave-buoy interaction problem with a robust implicit finite-difference method for the cable-buoy dynamics. The numerical scheme accounts for nonlinear wave-wave and wave-body interactions up to an arbitrary high order in the wave steepness and is able to treat extreme motions of the cable including conditions of negative cable tension. Systematic simulations show that beyond a small threshold value of the incident wave amplitude, the buoy performs chaotic motions, characterized by the snapping of the cable. The root cause of the chaotic response is the interplay between the snapping of the cable and the generation of surface waves, which provides a source of strong (radiation) damping. As a result of this interaction, the chaotic buoy motion switches between two competing modes of snapping response: one with larger average peak amplitude and lower characteristic frequency, and the other with smaller amplitude and higher frequency. The generated high-harmonic/short surface waves are greatly amplified once the chaotic motion sets in. Analyses of the radiated wave spectra show significant energy at higher frequencies which is orders of magnitude larger than can be expected from nonlinear generation under regular motion. 2005-08-23T05:57:23Z 2005-08-23T05:57:23Z 1999 Article http://hdl.handle.net/1721.1/25617 Journal of Fluid Mechanics, 381, p.305-335 (1999) en_US Copyright: Cambridge University Press This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder. 1462731 bytes application/pdf application/pdf Cambridge University Press |
| spellingShingle | surface buoy nonlinear short-wave numerical simulation Zhu, Q. Liu, Y. Tjavaras, A.A. Triantafyllou, M.S. Yue, D.K.P. Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title | Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title_full | Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title_fullStr | Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title_full_unstemmed | Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title_short | Mechanics of nonlinear short-wave generation by a moored near-surface buoy |
| title_sort | mechanics of nonlinear short wave generation by a moored near surface buoy |
| topic | surface buoy nonlinear short-wave numerical simulation |
| url | http://hdl.handle.net/1721.1/25617 |
| work_keys_str_mv | AT zhuq mechanicsofnonlinearshortwavegenerationbyamoorednearsurfacebuoy AT liuy mechanicsofnonlinearshortwavegenerationbyamoorednearsurfacebuoy AT tjavarasaa mechanicsofnonlinearshortwavegenerationbyamoorednearsurfacebuoy AT triantafylloums mechanicsofnonlinearshortwavegenerationbyamoorednearsurfacebuoy AT yuedkp mechanicsofnonlinearshortwavegenerationbyamoorednearsurfacebuoy |