Time domain simulations of the wave-induced motions of ships in maneuvering condition

The wave-induced motions of ships in maneuvering condition are numerically studied based on potential theory. The total disturbance potential is decomposed into a basic part and a perturbation part. The basic flow is evaluated based on the double-body model with a trailing vortex sheet. The perturbation flow is solved by using a time domain Rankine panel method to determine the hydrodynamic forces, and the wave-induced ship motions are then evaluated by an Adam-Moulton scheme. The solving process of the wave-induced motion is integrated with the maneuvering prediction by using a two-time scale model. Numerical tests are firstly carried out for a Series 60 ship, and the numerical results are compared with the experimental data to validate the numerical method for the basic flow. Then the wave-induced motions of the S-175 container ship in straight course and in turning condition are simulated; the numerical results are compared with the ITTC data and the experimental data, which show fairly good agreements.