Abstract
Wind-assisted propulsion is deemed to be a potential way to effectively reduce CO2 emissions in ship navigation. Some studies are discussing the characteristics of different sail types and their thrust performance, but a systematic investigation on the features of a multiple-sail system is insufficient, especially the effects of sail geometry and position on lift and drag. In this study, three arc-shaped sails are selected, and the geometric and spacing parameters are chosen as variables. The Computational Fluid Dynamics (CFD) method is applied to perform the simulations. The 2D overset mesh technique is applied to allow convenient mesh rotations. One sail alone is first investigated to find the best attack angle, and three sails with consistent attack angles and even mast distance are studied afterward. Finally, the Design of Experiment (DOE) is implemented to evaluate the significance level of the variables. Based on the results, it shows that the sails interaction can provide both positive and negative effects on the thrust performance. The distance between Sail 1 and Sail 2, the attack angle of Sail 1 and Sail 2 are significant factors impacting the thrust of the three-sail propulsion system. The mechanism of the interaction effects on the lift is also addressed. This study helps to find the predominant parameters affecting sail thrust performance and contributes to an intelligent manipulation of a multiple-sail propulsion system.
