螺旋桨毂帽鳍节能性能的数值模拟

毂帽鳍作为一种新型的船用节能装置，合理地安排其在桨后的位置，能明显提升螺旋桨的推进效率，因此，有必要对毂帽鳍的节能效果进行研究。采用计算流体动力学方法，对毂帽鳍的敞水性能进行模拟。通过改变鳍叶在桨后的各个参数，分析其尾流的变化，以及各重要剖面处的压力分布等情况。模拟结果表明：鳍叶的不同安装角位置对桨的效率变化有明显的影响，而轴向位置的改变则对其效率的提高影响不大。通过观察尾流分布及压力分布图，可以直观地看出鳍叶的主要功效是产生与螺旋桨转向相同的扭矩，同时使尾流速度降低从而削弱乃至消除毂涡。

Numerical Simulation of the Energy-Saving Performance ofPropeller Boss Cap Fins

As a novel marine energy-saving device,the Propeller Boss Cap Fins（PBCF）is often properlyinstalled behind the propeller to boost the propulsion efficiency of the propeller. As a result,the researchon the energy-saving effects of PBCF is of vital importance. In this paper,a computational fluid dynamicssoftware is adopted to simulate the open water performance of the fins. By changing the various parametersof the fins on the back of the propeller,the corresponding changes of wakes,the pressure distribution atcritical sections and other performance factors are analyzed. The results show that the different fix angles offins significantly impact the propulsion efficiency,while the change of axial positions produces little effect.Also,by observing the diagrams of wake distribution and pressure distribution,it could be concluded thatthe major function of fins is to produce certain torque on the same direction as the propeller and to reducewake speed so that the hub vortex may be weakened or even eliminated.