Experimental study of the interaction of wind with a wave induced by a wave producer in a direct channel

Abstract

An experimental study of the effect of wind blowing a wave induced by a wave generator in a direct channel has been carried out. It is shown that at low wave steepness 𝑎𝑘 < 0.1 and wind speed 𝑊 < 2.3 m/s, a drift current occurs on the water surface due to the influence of viscous forces. A formula for calculating its velocity is proposed. It is found that the phase velocity of the wave increases with the appearance of a drift flow and can be calculated using the formula obtained for linear waves on a flow with a constant velocity shift. With an increase in the steepness of the wave 𝑎𝑘 > 0.19 and an increase in wind 𝑊 > 2.3 m/s, the formation of a vortex deforming the water surface was detected in the air flow above the top of the wave crest. The vortex destroys the viscous layer, reducing the drift velocity. At the same time, the phase velocity and wavelength decrease. A mechanism explaining this process is proposed.