臺灣博碩士論文加值系統

　　本文主要目的，是於斜軸螺槳前設計一非對稱導流翼，以改善斜軸螺槳入流，使其一方面回收螺槳諀所損失之動態、降低螺槳所產生之垂向力，以增加快艇斜軸螺槳之推進效率，另一方面改善其空泡現象。
　　本文將使用由海洋大學造船系辛敬業博士所發展之升力線程式，計算非對稱導流翼與螺槳交互影響下，各別之最佳環流分佈：並使用MIT 之PBD10程式計算螺槳之幾何分佈。
　　此螺槳與非對稱導流翼模型於海大中型空蝕水槽進行測試，且與相同設計狀況單獨最佳化之新翼型（new section）螺槳作比較。
　　由實驗結果顯示：於設計負載狀況下螺槳與非對稱導流翼組較其螺槳單獨運轉之效率高6.3%，同時空泡現象有明顯改善，若與相同設計狀況之新翼形螺槳相比則效率高出6.3%。另外值得注意者是於設計點附近，非對稱導流翼產生之轉矩約為螺槳之58.2%，而產生之舉升力約為螺槳推力之35%；其螺槳產生之垂向力約為推力之18.3%，較單獨螺槳少三分之一。

　　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.