Numerical analysis on three-dimensional green water events induced by freak waves

Abstract

ABSTRACT Freak waves are a type of extreme waves with great wave heights and concentrated energies. When they encounter ships, large amounts of water flow onto deck and lead to strong impact pressures, threatening the structural safety significantly. Many efforts concerned about green water phenomena, while few of them focused on that induced by freak waves. This paper investigates the green water events induced by freak waves in three-dimensional numerical wave tank, which is validated well against experimental data under regular waves. The Peregrine breather solution model is applied to simulate freak wave and a 3D hull structure is modelled to head it. In this study, the water motion scenario is observed and several characteristic stages are classified. The impact pressures on deck and superstructure are analysed and the three-dimensional effect is discussed. At last, the features and dangerous moments of this type of green water events are concluded.