本研究中，在卡氏座標中使用直接沉浸邊界法模擬水平風力發電機的流固耦合，並且採用不規則網格。針對風機這一複雜幾何結構，本研究使用基於標準鑲嵌語言法(Standard Tessellation Language (STL))格式的三角形表面網格的幾何標記法來重構沉浸邊界。

本研究同時模擬了有支撐塔和沒有支撐塔的風機，發現支撐塔不僅僅提供支撐，並且會對風機的能源效率和葉片的動力係數有所影響。基於不同雷諾數的模擬（Re=500以及Re=1500）也在本研究中展現。為了分析風機的能源效率（C_p）以及風機葉片的空氣動力係數，本研究使用λ-C_p圖來展示，得到最佳的葉尖速率（Tip Speed Ratio（TSR）:λ）。

In the present study, the fluid-structure interaction of a horizontal wind turbine is simulated by using a direct forcing immersed boundary scheme. The Cartesian coordinate with non-uniform grid is adopted. In order to deal with the complex-shape of the wind turbine, the geometry tagging method of reconstruction immersed boundary with the triangular facet surface is added into the numerical model.
The cases with and without the tower are simulated. The fluid field is investigated at different Reynold numbers Re=500 and Re=1500. The tip speed ratio λ in both cases are kept at 7.0. To analyze the power coefficient (C_p) of the wind turbine and the aerodynamic characteristic of turbine blades, the effects of turbine efficiency are examined using the λ-C_p map.

Abstract i
Contents iii
List of Figures iv
List of Tables vii
1. Introduction 1
1.1 Introduction 1
1.2 Literature Survey 2
1.3 Objectives and Motivations 6
2 Numerical Methods 7
2.1 Immersed-Boundary Method 7
2.2 Geometry tagging algorithm 12
2.3 Complete solution procedure 18
3. Simulation of wind turbine 32
3.1 Structural properties of the wind turbine 32
3.2 Mesh design and setup 32
3.3 Results and discussion 35
4. Conclusions 57

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