Impacts of rudder profiles on ship manoeuvrability

The performance of a ship’s rudder largely determines its manoeuvrability, which includes turning ability, initial turning ability, yaw-checking ability and course-keeping ability. However, existing empirical formulas for rudder forces do not concern the rudder profile. This paper discusses the impacts of various rudder profiles on ship manoeuvrability. Instead of empirical formulas for rudder characteristics, Computational Fluid Dynamic methods (CFD) are applied to obtain lift and drag coefficients of five profiles. Then, the normal force coefficient of each profile is calculated and corrected for the aspect ratio. Commercial packages Pointwise and ANSYS ICEM generate the unstructured and structured mesh, respectively. ANSYS Fluent solves the Navier-Stokes equations. 2D steady-state viscous simulations of rudders in incompressible water are carried out with the k-w SST turbulence model. To test the impacts on manoeuvrability, a manoeuvring model is built in Python for the KVLCC2 tanker in deep water. Turning circle manoeuvres and zigzag manoeuvres are performed to compare the manoeuvring parameters. This paper concludes with insights into the impacts of rudder profiles on ship manoeuvrability.