Study on chaotic motion of ship with water on deck using random Melnikov method

Chaotic motion of ship with water on deck is studied using random Melnikov method and Poincare’ map. The roll motion equation of ship in random beam wave is established with considering the effect of trapped water on deck on static stability of ship.The parameter region for chaotic motion of ship is determined by random Melnikov process and mean-square criterion. The Poincare’ map and time history of roll response are calculated in different parameter regions. The results show that the chaotic motion can be restrained when increasing the ship damping. The Poincare’ map of ship roll response has two attraction domains and the roll process has two roll centers when considering the effect of water on deck. In the no-chaotic parameter region, ship rolls around one roll center. In the chaotic parameter region, the random jumping occurs from one roll center to another.