A study on ship performance in waves using a RANS solver, part 1: Comparison of power prediction methods in regular waves

摘要

Numerical analyses were performed on a KVLCC2 (Korea Research Institute of Ships and Ocean (KRISO) Very Large Crude oil Carrier 2) at Fr = 0.092 and 0.037 in regular wave conditions. A Reynolds averaged Navier-Stokes (RANS) solver was applied with the finite volume method and a realizable k-ε model as a turbulence model. The Volume of Fluid (VOF) equation was solved to implement the free surface. The body-force propeller method of the Virtual Disk model was used to represent the effect of the propeller and reduce the computation time significantly. Resistance and self-propulsion computations were carried out in calm water and regular head waves, and the results were verified by comparing them to the added resistance and motions from experiments. To find the trend of the delivered horsepower (DHP) in regular waves, regular head waves from the short wave to long wave conditions with two different wave steepness were considered. The load variation method was also performed using the obtained added resistance, and the resulting self-propulsion points were compared with the CFD results. In each wave case, the propulsive coefficients and DHP were also compared, and we discuss the relationship between the thrust deduction factor and wake fraction factor according to the wave conditions.