相對於水平軸式風機，垂直軸式風機擁有諸多優點，如不需要對風設計、噪音較低等，但由於最重要的輸出功率較低，使得垂直軸風機在發電上的應用較少。因此，許多人投入提高垂直軸風機功率的研究，從針對風機本體的葉片構型、造型改變，乃至於複合式設計以及外罩加強。本研究的目的在於設計針對垂直軸風機的全向式導流器(Omni-Directional Guide Vane, ODGV)，針對其設計參數作探討，找出最能增進風機性能的組合。分析方面是採數值模擬的方式，以計算流體力學軟體ANSYS CFX模擬風洞及模型的流場。CFX以有限體積法求解三維Reynolds Average Navier-Stokes方程式，並配合SST紊流模型；模擬的網格則是以ICEM CFD軟體建構四面體非結構網格，並在邊界以菱柱型網格加密以模擬邊界層。主要分析的重點是ODGV的導流板擺放角度以及入口流道的高度變化，分析結果也顯示兩者在設計上的確是重要的參數，對於ODGV的性能有很大的影響，可供往後的設計參考。

Compared to Horizontal axis wind turbine, vertical axis wind turbine has many advantages like yaw-mechanism-free and low noise level. But because of the major disadvantage – lower power output, applications of VAWT in power generator are less. Many people try to improve the performance of VAWT, from the VAWT blade studies, shape design, to hybrid configuration and shroud. The purpose of this research is to design VAWT-compatible Omni-Directional Guide Vane, ODGV. Discuss the design parameters and find out the combination that improves more performance of VAWT than other models. Computational Fluid Dynamics software ANSYS CFX is used to analyze and simulate the flow field in the calculation area. It solves three dimensional Reynolds Average Navier-stokes equation with finite volume method and the turbulence model is shear stress transport (SST). The mesh used in simulation is built by ICEM CFD. It consists mainly tetrahedral non-structural elements and prims elements near walls. The main analysis point is the vane orientation angle and height increment of inlet passage of ODGV. The results show that these two parameters have great influence on ODGV performance.

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