Freak wave in a two-dimensional directional wavefield with bottom topography change. Part 1. Normal incidence wave

In the propagation and evolution of sea waves, previous studies pointed out that occurrence freak wave height is significantly related to quasi-resonant four-wave interaction in modulated waves. From numerical--experimental study over an uneven bottom, nonlinear effect caused by bathymetry change also contributes extreme events unidirectional To comprehensively analyse two-dimensional wavefield, this develops model for a directional random wavefield based on depth-modified Schrödinger equation, which considers resonant interactions shoaling shallow water. Through Monte Carlo simulation, we discuss train maximum distribution from deep water with slow varying slope. The numerical result indicates spreading has dispersion height. shallow-water environment, becomes weak, bottom topography main influencing factor evolution.