Experimental Study on Ship-Bank Interaction of Very Large Crude Carrier in Shallow Water

In order to assess the influence of ship-bank interaction on ship manoeuvring motion, planar motion mechanism (PMM) tests on a scale model of the KRISO very large crude carrier (KVLCC2) are conducted in different water depths in circulating water channel (CWC). The asymmetric hydrodynamic derivatives are defined to characterize the bank effect, and they are measured through the straight towing test with varying lateral displacements. The linear and nonlinear hydrodynamic derivatives are determined from the test data of the Fourier integral and mathematical regression model. The rudder and heading angles required at equilibrium conditions in different ship-bank distances are calculated by the manoeuvring model. The directional stability with varying ship-bank distances is studied in terms of eigenvalue analysis. Analysis based on the test results shows that the KVLCC2 model ship appears inherently unstable for keeping course in deep and shallow water conditions. When the ship-bank distance decreases, the increasing ship-bank interaction can dramatically affect some parameters of the criteria for course keeping.