Large parametric rolling of a large passenger ship in beam seas and the role of bilge keel in its restraint

Abstract

Model experiments of a scale model of a large passenger ship without bilge keels in beam seas demonstrate that parametric roll resonance with roll amplitude can reach more than 25 degrees occurs in the range of short waves. It is identified that the change of wave height affects the change of metacentric height in waves so that it affects the occurrence of the parametric rolling in beam seas. It is experimentally confirmed that the designed bilge keels for the ship can restrain such parametric rolling. Moreover, the experiments with various sizes of bilge keels show that they can affect the occurrence of parametric rolling in beam seas.