螺旋桨与毂帽鳍集成一体化优化设计方法研究

  目的  随着绿色船舶理念的兴起，船舶水动力节能技术逐渐成为研究的热点。为降低船舶航行中的能耗，  方法  采用上海交通大学万德成教授课题组自主开发的naoe-FOAM-SJTU求解器，对毂帽鳍的水动力特性进行预报；为了更好地考察毂帽鳍与螺旋桨之间的相互影响，计算时分别考察毂帽鳍对桨叶、桨毂以及毂帽的影响。  结果  结果显示，桨毂和毂帽受毂帽鳍的影响较小，毂帽鳍可明显降低螺旋桨扭矩，但对推力的影响较小；进一步研究发现，雷诺数对毂帽鳍的节能特性具有较大影响且存在着一个临界值，当低于临界值时，随着雷诺数的增加，其节能效果会有较大的提升，而在达到临界值后，其节能效果基本保持不变，从侧面说明了在达到临界雷诺数的实尺度时，毂帽鳍会有更好的节能特性。  结论  研究充分证明采用naoe-FOAM-SJTU求解器研究毂帽鳍的节能特性可靠，可为更多种类的节能装置研究提供参考。

Research on integrated optimal design method of propeller and PBCF(Propeller Boss Cap Fins)

  Objectives  With the increasing popularity of the concept of green ships, marine hydrodynamic energy-saving technology has drawn more attention from researchers. This paper studies the way to reduce energy consumption of ships at sea.  Methods  naoe-FOAM-SJTU solver independently developed by Prof. Wan Decheng's research team in Shanghai Jiao Tong University is used to numerically investigate the hydrodynamic characteristics of Propeller Boss Cap Fins (PBCF). In order to better investigate the interaction between PBCF and propeller, the influences of PBCF on blades, hubs and hub caps are studied respectively.  Results  It is found that the hubs and hub caps are less affected by PBCF, and despite sharp reduction of the propeller torque, the influence of PBCF on the overall thrust is limited. Further it is found that the Reynolds number has great influence on the energy-saving characteristic of PBCF and has a critical value below which the increasing Reynolds number will give rise to greatly improved energy-saving effect, and above which, the energy-saving effect is basically unchanged. This shows that PBCF may have better energy-saving characteristics in the full scale which has the critical Reynolds number.  Conclusions  The findings are satisfactory and shows that the naoe-FOAM-SJTU solver is feasible for the direct simulation of hydrodynamic characteristics of PBCF, and this research method can be applied to other energy-saving devices.