Nonlinear aspects of the motion behavior of directional wave buoys
- Naval Research Lab., Washington, DC (United States). Remote Sensing Division
- National Data Buoy Center, Stennis Space Center, MS (United States). Engineering Division
The possibility of nonlinear behavior in the motions of two classes of widely used directional wave buoys is investigated. One is a spherical buoy with a large underwater drag sting. The other is the National Data Buoy Center (NDBC) 3-meter (10-ft) discuss buoy. The motions of the buoys are calculated by using a time domain model and a frequency domain model which uses an equivalent linearization technique to approximate the nonlinear hydrodynamic drag. The existence of nonlinear behavior is determined by directly examining the output of the equivalent linearization code, and by using Hilbert and spectral analysis techniques on the output of the time domain code. It is found that the motions of the discuss buoy are only weakly nonlinear. In particular, the motion transfer functions show only moderately small variations in different sea states. The spherical buoy pitch motion shows strongly nonlinear behavior in the presence of high sea states. In these cases, the buoy pitch transfer function shows a strong dependence on the wave height which is used.
- OSTI ID:
- 55686
- Report Number(s):
- CONF-940230-; ISBN 0-7918-1264-2; TRN: IM9525%%367
- Resource Relation:
- Conference: 13. international conference on offshore mechanics and Arctic engineering (OMAE-13), Houston, TX (United States), 27 Feb - 3 Mar 1994; Other Information: PBD: 1994; Related Information: Is Part Of OMAE 1994. Volume 1: Offshore technology; Chakrabarti, S.K.; Morrison, D.; Williams, A.N.; Ertekin, R.C.; Maeda, Hisaaki; Pantazopoulos, M.S. [eds.]; PB: 492 p.
- Country of Publication:
- United States
- Language:
- English
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