A New Model on Equilibrium Spectrum of Wind Waves

Abstract : Based on the joint-distribution of wave amplitude and wave period, a new model on the equilibrium spectrum of wind waves is derived. The derived model is related to the wind speed, spectral width and wave age. The related coefficients are determined empirically based on the observation. This model can be used to explain the variability of spectral level and spectral curve slope. It is found that the spectral level is controlled by both wind speed and wave age; the slope of spectral curve is related to only the wave age. The relationships between the spectral width and wave age, between the spectral level and wave age are obtained based on the spectral properties and empirical observations.