Abstract With the implementation of an energy efficiency design index, energy-saving devices (ESDs) have received increasing research interest. In this study, experimental and numerical analyses were performed on a 25-m long ore carrier model to investigate the working mechanism of ESDs comprising a pre-swirl stator and a rudder bulb. The interactions between the hull, propeller, rudder, and ESDs were observed to have a positive effect on the propulsion performance of the large-scale ship model. To elucidate the effects, self-propulsion tests were conducted at sea to determine the thrust and torque coefficients. The sliding mesh method was used to perform numerical simulations of the large-scale ship model for unsteady multiphase flows with different inflow speeds. The wake field at the stern and the pressure distribution on the vessel surface were analysed to investigate the energy-saving mechanism. The results showed that ESDs can effectively ameliorate the propeller slipstream and have a positive interference effect on the large-scale hull. The average gain of the ESDs relative to no-ESDs was up to 3%.

中文翻译：

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预涡流定舵球系统对大型船模推进性能的影响

摘要 随着能效设计指标的实施，节能装置（ESD）受到越来越多的研究关注。在这项研究中，对 25 米长的矿石载体模型进行了实验和数值分析，以研究由预旋定子和舵球组成的 ESD 的工作机制。观察到船体、螺旋桨、舵和 ESD 之间的相互作用对大型船模型的推进性能产生积极影响。为了阐明这些影响，在海上进行了自航试验以确定推力和扭矩系数。采用滑动网格法对具有不同流入速度的非定常多相流的大型船模进行数值模拟。分析了船尾尾流场和船舶表面压力分布，研究了节能机制。结果表明ESDs能有效改善螺旋桨滑流，对大型船体具有正向干扰作用。相对于无 ESD，ESD 的平均增益高达 3%。