INTERACTION OF WIND WITH SURFACE WATER WAVES

• Published in: Neural, parallel & scientific computations parallel & scientific computations, 2014-09, Vol.22 (3), p.303-314
• Main Authors: DRULLION, F, Sajjadi, S G
• Format: Article
• Language: English
• Subjects: Age; Computation; Computer simulation; Disturbances; Orbital velocity; Steepness; Surface water; Water waves
• ISSN: 1061-5369

A turbulent flow over different growing and non growing water waves is considered by constructing a high-Reynolds-number stress closure model. The profile of the water wave as well as the associated orbital velocities are prescribed. In the case of a growing wave, the profile and the orbital velocities can change dynamically under the action of the wind blowing above the wave. This work focuses on the influence of the wave age (ratio of the wave speed over the wall friction velocity) and the wave steepness on the dynamics of the critical layer (the region about the height at which the real part of the complex wave phase speed is equal to the mean flow velocity) and on region of close streamlines, called cat's eye patterns that are created above the surface of the wave and is centered about the critical layer. The simulations show that the height of the critical layer increases with the wave age and the steepness of the wave, what is in agreement with the direct numerical simulations reported by Sullivan et al.[21]. The cat's eye patterns increase in size and extend vertically with the increase of the wave age and lead to a maximum disturbance of the mean flow for older waves. The model being computationally less expensive than a DNS approach, it allowed us to study waves growing under the influence of the wind. The simulations show that as the wave grows the critical layer elevates and the cat's eye structures become larger leading again to an important disturbance of the wind flow above the wave.