論文名稱:

小型Savonius螺旋式葉片設計與模擬分析

Design and Numerical Analysis of Small Helical Savonius Rotors

研究生:

楊志煌

指導教授:

楊士震

毛祚飛

          學號:

98017008

畢業學年度:

99

      出版年:

民100

關鍵字:

螺旋式葉片 spiral blades

計算流體力學 computational fluid dynamics

扭力係數 torque coefficient

摘要:

傳統垂直軸式Savonius型風力發電機主要是利用氣流在風力機葉片前、後壓力差形成阻力以推動葉片旋轉，雖然啟動轉矩大，但葉片在旋轉過程中會發生負扭力值，降低風能利用效率，本文利用快速成型技術製作小型Savonius螺旋式葉片模型，配合風洞實驗與計算流體力學方法，探討不同葉片扭角之空氣動力行為與扭力分佈特性，數值模擬使用Ansys Fluent 分析軟體，進行小型Savonius風力發電機螺旋式葉片暫態流場與氣動分析；在實驗量測方面，利用自行設計組立的低風速風洞設備進行風洞量測實驗，本文改變螺旋式葉片扭角0度、90度與180度進行Savonius螺旋式葉片扭力測試，實驗結果顯示改變葉片扭角可以有效改善傳統Savonius型風機葉片在運轉過程中負扭力值，螺旋角90度的葉片在不同風速6、8、10、12m/s時之轉速與平均扭力係數為最高，當螺旋角為180度時可以完全消除葉片負扭力值，經由模擬與實驗結果比較，可以驗證本文提出Savonius型風機葉片螺旋角設計與實驗分析的可行性。

The air pressure difference between upper and bottom of the rotors is the thrust for the rotation of traditional vertical axis Savonius-type wind turbine. The starting torque for Savonius-type wind turbine is large. However, the negative torque value can occur during the rotating process, reducing the efficiency of wind energy utilization. In this study, the rapid prototyping technology (RP) is used to produce small type Savonius helical rotor. The experimental and simulation methods are performed to explore the aerodynamic and the torque characteristics of helical rotor with different helix angles. Numerical simulation software Ansys Fluent is performed to simulate the transient flow field and aerodynamic in all cases. The low-speed wind tunnel test equipment designed in this study is used for the experimental measurement. Three helix angle of 0 degrees, 90 degrees and 180 degrees are performed in the experimental tests. The experimental results show that the helical rotor can improve the negative torque value of traditional Savonius type wind turbine during operation. The rotation speed and average torque coefficient are highest with the helix angle of 90 degrees at the wind speeds of 6,8,10,12 m/s. For the helix angle of 180 degrees, the negative torque can completely eliminate. From the simulation and experimental results, we show the design feasibility of  Savonius-type helical rotor wind turbine.