Research On Simulation Of Ship Maneuvering-swaying Coupling Motion Of 6-DOF In Waves

This paper researches on the ship 6-DOF maneuvering-swaying coupling motion in waves. Movement of ships in waves is simulated by the simulation programs which are built on the basis of mathematical model and the impact of waves on ship motion is reasearched.A new mathematical model of the ship 6-DOF motion on Horizontal Body Axes coordinates is derived in this paper. The model does not consider coupling of the inertial force, viscous force, propeller thrust, rudder force and wave forces based on the view of MMG. Hydrodynamicforce of the swaying motion is calculated by STF method, wave exciting force calculated by three-dimensional element surface method and wave second-order force calculated by the empirical equation.Comparing the simulation results and experimental results of ship motion verifies the correctness of the mathematical model. The comparing results confirmed that the simulation results of ship motion in waves and in calm water based on the mathematical models are realistic and credible enough to simulate ship maneuvering-swaying coupling motion in waves.Through extensive simulation, this paper finds three typical trajectories of ship turning navigations in waves, and makes two volume-the instantaneous turning center point and the instantaneous turning radius-to analyze the drift and stability of ship turning navigation in waves. This paper researches on the different components of the wave forces and waves of different height, length and angle on the effects of ship motion. According to results of the analysis, this paper makes some conclusions which can guide ship-handling in waves which are engineering valuable.Finally some suggestions is tabled for the lack of the mathematical model.