Features of Wind Wave–Induced Turbulence in Water According to Measurements in a Wind-Wave Tank

AbstractIt is important to develop a wave-generation method for extending the fetch in laboratory experiments, because previous laboratory studies were limited to the fetch shorter than several dozen meters. A new wave-generation method is proposed for generating wind waves under long-fetch conditions in a wind-wave tank, using a programmable irregular-wave generator. This new method is named a loop-type wave-generation method (LTWGM), because the waves with wave characteristics close to the wind waves measured at the end of the tank are reproduced at the entrance of the tank by the programmable irregular-wave generator and the mechanical wave generation is repeated at the entrance in order to increase the fetch. Water-level fluctuation is measured at both normal and extremely high wind speeds using resistance-type wave gauges. The results show that, at both wind speeds, LTWGM can produce wind waves with long fetches exceeding the length of the wind-wave tank. It is observed that the spectrum of wind waves with a long fetch reproduced by a wave generator is consistent with that of pure wind-driven waves without a wave generator. The fetch laws between the significant wave height and the peak frequency are also confirmed for the wind waves under long-fetch conditions. This implies that the ideal wind waves under long-fetch conditions can be reproduced using LTWGM with the programmable irregular-wave generator.

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Control of wind/wave-induced vibrations of jacket-type offshore wind turbines through tuned liquid column gas dampers

Structure and Infrastructure Engineering ◽

10.1080/15732479.2015.1011169 ◽

2015 ◽

Vol 12 (3) ◽

pp. 312-326 ◽

Cited By ~ 11

Author(s):

Reza Dezvareh ◽

Khosrow Bargi ◽

Seyed Amin Mousavi

Keyword(s):

Wind Turbines ◽

Wind Wave ◽

Liquid Column ◽

Offshore Wind ◽

Offshore Wind Turbines ◽

Wave Induced

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Turbulent current measurements in a wind-wave tank

Journal of Geophysical Research Atmospheres ◽

10.1029/jc089ic01p00627 ◽

1984 ◽

Vol 89 (C1) ◽

pp. 627 ◽

Cited By ~ 15

Author(s):

Jung-Tai Lin ◽

Mohamed Gad-el-Hak

Keyword(s):

Wind Wave ◽

Wave Tank

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A wind-wave tank study of the azimuthal response of a Ka-band scatterometer

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/36.103304 ◽

1991 ◽

Vol 29 (1) ◽

pp. 143-148 ◽

Cited By ~ 18

Author(s):

J.-P. Giovanangeli ◽

L.F. Bliven ◽

O. Le Calve

Keyword(s):

Wind Wave ◽

Wave Tank ◽

Ka Band

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Statistical Parameters of the Air Turbulent Boundary Layer over Steep Water Waves Measured by the PIV Technique

Journal of Physical Oceanography ◽

10.1175/2011jpo4392.1 ◽

2011 ◽

Vol 41 (8) ◽

pp. 1421-1454 ◽

Cited By ~ 19

Author(s):

Yu. Troitskaya ◽

D. Sergeev ◽

O. Ermakova ◽

G. Balandina

Keyword(s):

Boundary Layer ◽

Turbulent Boundary Layer ◽

Interaction Parameter ◽

Water Waves ◽

Water Surface ◽

Wind Wave ◽

Wave Interaction ◽

Statistical Parameters ◽

Piv Technique ◽

Wave Induced

Abstract A turbulent airflow with a centerline velocity of 4 m s−1 above 2.5-Hz mechanically generated gravity waves of different amplitudes has been studied in experiments using the particle image velocimetry (PIV) technique. Direct measurements of the instantaneous flow velocity fields above a curvilinear interface demonstrating flow separation are presented. Because the airflow above the wavy water surface is turbulent and nonstationary, the individual vector fields are conditionally averaged sampled on the phase of the water elevation. The flow patterns of the phase-averaged fields are relatively smooth. Because the averaged flow does not show any strongly nonlinear effects, the quasi-linear approximation can be used. The parameters obtained by the flow averaging are compared with the theoretical results obtained within the theoretical quasi-linear model of a turbulent boundary layer above the wavy water surface. The wave-induced pressure disturbances in the airflow are calculated using the retrieved statistical ensemble of wind flow velocities. The energy flux from the wind to waves and the wind–wave interaction parameter are estimated using the obtained wave-induced pressure disturbances. The estimated values of the wind–wave interaction parameter are in a good agreement with the theory.

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