Surf zone wave modeling - Validation and improvement of dissipation by depth-induced wave breaking in swan

Abstract

This research is based on the shallow water wave model SWAN (Simulating WAves Nearshore), a third-generation wave model that solves the action balance equation with sources and sinks.In the first part of this research, validation of SWAN is carried out through three computational schemes. The second part of this thesis aims to improve the prediction accuracy of SWAN in shallow waters by developing a better dissipation model for depth-induced breaking.To address both shortcomings of the underlying truncated Rayleigh pdf and the hydraulic jump assumption, a new dissipation equation for wave height transformation has been formulated based on the breaking wave height distribution by Thornton and Guza (1983) and the dissipation model by Rattanapitikon W. & Shibayama T. (1998).Dissipation models by various authors and the newly derived dissipation formulation are implemented into the SWAN code to make inter-comparisons and to verify results against experimental data reported by Battjes and Janssen (1978).