Performance of a Magnus effect-based cylindrical roll stabilizer on a full-scale Motor-yacht

Abstract

The rotor stabilizer systems based on the Magnus principle are among the alternative systems used as an anti-rolling system. The key objective of this paper is to extensively study the performance of the Magnus stabilizer on a ship's roll-heave motions in a regular beam sea and at low velocity, as well as to investigate the hydrodynamic characteristics of the rotating cylinder in the varied diameters and rotation speeds. Two-dimensional rotating cylinders and three-dimensional ship-rotor cases are simulated using the RANS solver by adopting SST k-ω turbulence model. Flow past a rotating cylinder is computed with cylinder diameter-based Reynolds Numbers of 7.33 × 105, 1.01 × 106 and 1.26 × 106 in the spin ratio range of 1.52 < α < 13.09. The rotational motion of the cylinder is simulated by the rotating wall approach. The lift forces obtained from two-dimensional analyses are applied externally as damping moments to examine the effect of Magnus stabilizer on the dynamic motions of the full-scale motor yacht. The results indicate that the increased diameter is effective on the lift force than increased rotation speed. The ship-rotor interaction is successfully modeled by external moment application as a practical engineering approach. Magnus stabilizer presents a high-performance in roll reduction that varies between 9.13% and 85.84%.