A numerical study on the ship-bank interaction at various water depths of a surface ship.

Ship maneuvering in restricted waters is a significant challenge in navigation safety due to the complex flow around the ship. In particular, when a ship travels close to a lateral bank and shallow water, the hydrodynamic interaction forces significantly influence the maneuvering motion of the ship. Maneuverability in restricted water is even more difficult for an autonomous surface ship. Therefore, it is necessary to assess the effects of maneuvering near a bank and in shallow water for an autonomous surface ship. In this study, maneuvering simulations considering the bank effect at various water depths are implemented based on hydrodynamic forces estimated using computational fluid dynamics simulation. First, virtual captive model tests at various water depths and simulations of various lateral distances to the banks are performed to estimate the hydrodynamic forces using computational fluid dynamics simulation. The simulation method is validated by comparing the simulation results of the static drift test in deep water with the measured one in the experimental method. Second, the maneuvering simulations for the turning circle test and zig-zag test at various water depths are conducted using the obtained hydrodynamic coefficients. Then, the maneuvering simulations in deep water are compared with the experiment results, and a good agreement is observed. Finally, the simulation considering the bank effects at various water depths is evaluated and discussed.