Abstract
Whether or not ‘separation’ occurs in the airflow over wind-generated water waves is partly a question of semantics but also has an important bearing on the wave generation process. In the present paper we use a rather formal and perhaps narrow definition of ‘separation’ and show that it does not occur where the shear stress is zero but only in conjunction with wave breaking. This is unlikely to happen except in the presence of quite strong surface drift velocities in the water. A similar connection between separation, surface drift and wave breaking has recently been established by Banner and Melville (1976).
The effects of increasing wave amplitude or steepness are investigated with a numerical model of the airflow over water waves. Variations in the depth of the closed streamline region are predicted. The model is also used to investigate the possible importance of surface drift velocities.
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On leave 1976, Atmospheric Environment Service, Downsview, Ont., Canada.
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Gent, P.R., Taylor, P.A. A note on ‘separation’ over short wind waves. Boundary-Layer Meteorol 11, 65–87 (1977). https://doi.org/10.1007/BF00221825
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DOI: https://doi.org/10.1007/BF00221825