MECHANISM TO FORM WIND WAVES VIA AIR-WATER INTERACTIONS IN WIND/OCEAN BOUNDARY LAYERS

Abstract

 In this study, a three-dimensional large eddy simulation with a sharp interface model, based on ghost velocity extrapolations to fulfill dynamic boundary conditions at the interface, were performed to identify the interfacial instability to form water waves owing to turbulent wind. We found multiple pairs of helical counter-rotating vortices in the wind axis displace the interface to form extension of longitudinal scars aligned to the spanwise direction at critical wind velocity. Capillary waves are then created under spanwise vortex pairs appearing in the wind boundary layer.