毂帽鳍节能原理的CFD分析

CFD investigation on the energy-saving mechanism of propeller boss cap fins

随着绿色船舶理念的逐渐兴起,船舶水动力节能技术日益成为研究的热点。毂帽鳍是一种用于提升船舶螺旋桨推进效率的水动力节能装置,能够打散螺旋桨的毂涡,消除螺旋桨毂帽后端的低压区,是一种通过回收螺旋桨叶根部旋转尾流的能量从而达到节能目的的节能装置,因其具有良好的节能收益、成本低和施工方便等优点而受到了广泛的应用。传统上,主要采用模型试验的方法进行研究,但有着成本高、周期长等不足。随着计算机技术的发展,计算流体力学(CFD)越来越多地应用于节能装置的研究上。该文使用CFD开源的代码工具OpenFOAM对毂帽鳍的水动力性能进行了预报,计算中采用滑移网格技术进行流场的计算。通过对比有无毂帽鳍的两种情形下螺旋桨敞水特性,发现毂帽鳍能够有效地改善螺旋桨后尾流场,从而提升螺旋桨的推力,降低螺旋桨的扭矩,起到了明显的节能作用。

With the gradual rise of the concept of green ships,marine hydrodynamic energy-saving technology becomes a hot topic.Propeller boss cap fins（PBCF） is a kind of hydrodynamic energy-saving device used to improve propulsion efficiency of propeller.It can save energy by recycling the rotating energy of blade root of the propeller.It has been widely applied for its advantages such as good energy-saving effect,low manufacturing cost,convenient construction and so on.Traditionally,the study of PBCF is conducted using model test model which had the disadvantage of high cost and long study period.Along with the development of the computer technology,computational fluid dynamics is applied more and more to the study of the energy-saving devices.This paper uses the open software Open FOAM to do the hydrodynamic calculation on the PBCF.The sliding mesh is used in the calculation.Comparing the open water characteristics of the propeller with and without PBCF,it is found that PBCF could effectively improve the wake field of the propeller and obtain good energy-saving effect.