EVOLUTION OF THREE-DIMENSIONAL SURFACE FORMES OF INITIAL WIND WAVES

Abstract

 Evolution of planar surface forms of initial waves formed in wind tunnel experiments, measured by diffusive light photography, was discussed in this study. The initially created crossing small ripples evolve into larger waves with uniform wave crests with longer wave length propagating in the direction of wind, while a variety of wave forms are taken during the evolution; parastic capillary waves on the wave face, local ejection of the wave crest, resulting in spume drops. The energy transfers among frequencies and wavenumbers during the wave evolution were discussed on the basis of spatio-temporal spectrum.