Wind waves generation
Understanding the generation of surface waves under the action of wind is a problem of primary interest for wave forecasting and for evaluation of air-sea exchanges of heat, mass, and momentum on Earth or on natural satellites. It is also important in engineering applications involving
liquid and gas transport in pipes.
We investigate experimentally the early stage of the generation of waves by a turbulent
wind at the surface of a viscous liquid. The spatio-temporal structure of the surface
deformation is analyzed by the optical method Free Surface Synthetic Schlieren, which allows for time-resolved measurements with a micrometric accuracy.
Because
of the high viscosity of the liquid, the flow induced by the turbulent wind in the
liquid remains laminar, with weak surface drift velocity. Two regimes of deformation
of the liquid-air interface are identified. In the first regime, at low wind speed,
the surface is dominated by rapidly propagating disorganized wrinkles, elongated in
the streamwise direction, which correspond to the surface response to the pressure
fluctuations advected by the turbulent airflow. The amplitude of these deformations
increases approximately linearly with wind velocity and are essentially independent
of the fetch (distance along the channel). Above a threshold in wind speed, we observe
the growth of well defined gravity-capillary waves with crests nearly perpendicular to
the wind direction. In this second regime, the wave amplitude increases with wind
speed but far more quickly than in the first regime
Publications
- Kelvin-Helmholtz instability and formation of viscous solitons on highly viscous liquids
M. Aulnette, J. Zhang, M. Rabaud, F. Moisy, Phys. Rev. Fluids 7, 014003 (2022).
[Abstract | PDF]
- Effect of a weak current on wind-generated waves in the wrinkle regime
C. Nové-Josserand, S. Perrard, A. Lozano-Duran, M. Rabaud, M. Benzaquen, F. Moisy, Phys. Rev. Fluids 5, 124801 (2020).
[Abstract | PDF]
- Wind-sustained viscous solitons
M. Aulnette, M. Rabaud, F. Moisy, Phys. Rev. Fluids 4, 084003 (2019). Editor's suggestion
[Abstract | PDF]
- Turbulent windprint on a liquid surface
S. Perrard, A. Lozano-Duran, M. Rabaud, M. Benzaquen, F. Moisy, J. Fluid Mech. 873, 1020-1054 (2019).
[Abstract | PDF]
- Viscosity effects in wind wave generation
A. Paquier, F. Moisy and M. Rabaud, Phys. Rev. Fluids 1, 083901 (2016)
[Abstract | PDF]
- Surface deformations and wave generation by wind blowing over a viscous liquid
A. Paquier, F. Moisy, and M. Rabaud, Phys. Fluids 27, 122103 (2015)
[Abstract | PDF]
Thesis
- Ondes non linéaires générées par le vent à la surface d'un liquide visqueux
M. Aulnette, PhD thesis, Université Paris-Saclay (2021)
[Abstract | PDF]
- Generation and growth of wind waves over a viscous liquid
A. Paquier, PhD thesis, Université Paris-Saclay (2016)
[Abstract | PDF]
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