Numerical Simulation and Mechanism Analysis of Freak Waves in Random Oceanic Sea States

摘要

Numerical simulation of freak wave generation in random oceanic sea states described by JONSWAP spectrum is carried out based on the modified four-order nonlinear Schr?dinger (mNLS) equation in deep water. By comparison of the variation of each term modulus in mNLS equation and the power spectra for freak wave occurrences, it can be concluded that nonlinear focusing of some components with approximate frequencies to the dominant frequency is one possible mechanism of freak waves. Effects of the relevant parameters on freak wave formation are also discussed.