小型風力發電機已知是可以安置一個外罩以讓其達到性能大幅提升的目的，本研究以三維流體力學解析黏性流體Navier-Stokes方程式的方法，探討一具有外罩的小型風力發電機在不同葉片安裝角度下的性能特性，以期在廣泛的風速條件下均能夠有優異性能的發揮。
論文中探討的模型是以一具1KW額定輸出功率的小型風力發電機為基礎，風速範圍為2 m/s至50 m/s，安裝角度由基礎的角度為基準調整範圍由-10度至+60度，轉速則為固定。
研究的重點在於不同葉尖速比的條件下整體氣動扭力及功率的輸出與其效率的表現，並據以訂立在各種操作環境下的控制邏輯，以達風力發電機最佳性能發揮的基礎。論文中將討論數值仿真方法、物理模型、重要參數條件、結果的探討及建議達最佳性能發揮的控制邏輯，以做為未來設計者的參考。

It is well known that a shrouded wind turbine can result in significant improvement in aerodynamic performance over traditional designs. This research is intended to discuss a small wind turbine at various pitch angles, using three-dimensional computational fluid dynamics (CFD) to provide good performance of the wind turbine in a wide range of operating conditions.
The baseline model is a small wind turbine with a 1KW rated output. The wind velocity range in the study is from 2 m/s to 50 m/s. The pitch variation is from -10˚ to +60˚, based on the baseline design. The rotational speed is kept constant at all operating conditions. The major focus is to discuss the torque, power and efficiency output at various blade tip speed ratios (TSR). The obtained data are used to determine the control logic for blade pitch angle selection in order for the wind turbine to achieve the optimal aerodynamic performance.
In this thesis, the physical model, boundary conditions, numerical method, parametric effect, and finally suggestions for control logic to achieve the best performance over a wide operating range are discussed for design reference.

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