On the Efficiency Increase of Propeller at Inclined Shaft Condition by Using Asymmetric Stator

• Main Author: 李瓊惠
• Other Authors: 柯永澤
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/65182750072407903202

碩士 === 國立海洋大學 === 造船工程研究所 === 87 === 　　The purpose of this thesis is to design an asymmetric stator fixed in front of the propeller at inclined shaft condition. This stator-propeller device is used to improve the propeller inflow, and therefore the loss of rotational kinetic energy of propeller and the vertical force produced by the propeller can be reduced to improve the efficiency of the propeller. Furthermore, this kind of design can also reduce the propeller cavitation. 　　In this thesis, a lifting line program developed at NTOU (National Taiwan Ocean University) is first adopted for calculating the optimum circulation distribution of the asymmetric stator and the propeller, and MIT-PBD10 is then used to determine the detailed propeller geometry. 　　Experiments of the designed stator-propeller model have been performed in the Medium Cavitation Tunnel at NTOU. The experimental results have been compared with those of the optimized single propeller with the new section geometry at the same design condition. The experimental results show that the efficiency of stator-propeller is 6.3%higher than that of propeller alone when operating at design condition. The efficiency of the stator-propeller is also improved by 6.3% when comparing to the optimized single propeller with new section geoetry. Notice that the torque and lifting force produced by asymmetric stator are about 58.2%,and 35% of the propeller, respectively, at the design condition, and the vertical force produced by propeller is about 18.3% of the propeller thrust which is one third smaller than that of single propeller.