A numerical study of drift angle effect on hydrodynamic performance of a fully appended container ship in head waves

To accurately predict the ship’s manoeuvring and powering performance in actual seaways, it is crucial to gain an enhanced comprehension of the hydrodynamic behaviour of vessels navigating through waves. A critical component is the accurate determination of forces exerted on the hull and its appendages when the ship is operating at an angle of drift in waves. This is also significant for wind-assisted ships, which often operate with non-zero drift and rudder angles. Therefore, a deeper understanding of how drift and rudder angles affect hull–propeller–rudder interaction is required for investigating energy efficiency in waves. In this paper, a thorough numerical study is conducted to investigate the hydrodynamic interaction among the hull, propeller and rudder of the benchmark KRISO Container Ship (KCS) in regular head waves. The KCS is simulated at drift angles of −10°, 0°and +10°, combined with a series of rudder angles (−20°to +20°), representing quasi-static phases of actual ship manoeuvring in waves. Blade Element Momentum theory (BEMt) is adopted for modelling propeller action in all cases. Good agreement is found between experimental and numerical predictions regarding hull forces. This study contributes to better ship design due to ship manoeuvring and operations of wind-assisted vessels.