Spectral Model for Wave Transformation and Breaking over Irregular Bathymetry

Abstract

A numerical model is presented that predicts the evolution of a directional spectral sea state over a varying bathymetry using superposition of results of a parabolic monochromatic wave model run for each initial frequency-direction component. The model predicts dissipation due to wave breaking using a statistical breaking model and has been tested with existing data for unidirectional random waves breaking over a plane beach. Experiments were also conducted for a series of random directional waves breaking over a circular shoal to test the model in a two-dimensional wave field. The model performs well in both cases, although directional effects are not included in the breaking dissipation formulation.