本研究旨在優化葉片設計並評估採用具有扭曲中心線的扁平矩形葉片的小型三葉片 VAWT（垂直軸風力渦輪機）的空氣動力學性能。扭曲中心線模型的空氣動力學行為由商業 CFD（計算流體動力學）軟件 FLUENT 模擬，以產生控制因素的最佳組合，即葉片寬度、定位角度和高度。為了表徵流動特性，通過 CFD 模擬和田口分析進行了綜合研究，以優化選定的控制因素。結果發現控制因素的最佳組合為葉片寬度80mm，高度260mm，定位角00。通過GIT數值驗證表明，結果大部分時間收斂，網格劃分最大在當前模型分析中的影響可以忽略不計。當前的設計令人驚訝地比基準模型提高了 87.5% 的扭矩和 87.9% 的 Cp。在採用扭曲中心線設計時，觀察到的力波動不太明顯，這可能會導致渦輪機的使用壽命更長。從這項研究中獲得的輸出假設了一個更好、更簡單的 VAWT 設計，適用於風速相對較小的環境，如城市地區和農村生活區。

This research aims to optimize the blade design and estimate the aerodynamic performance of a small three-bladed VAWT (vertical axis wind turbine) adopting flat rectangular blades with a twisted centreline. Aerodynamic behaviors of the twisted-centreline model were simulated by the commercial CFD (computational fluid dynamics) software, FLUENT, to yield optimal combinations of control factors, namely blade width, positioning angle, and height. To characterize the flow characteristics, comprehensive studies were carried out by the CFD simulations and Taguchi analysis to optimize the selected control factors. As a result, the optimal combination of control factors was found to be blade width of 80mm, the height of 260mm, and the positioning angle of 00. Numerical validation through GIT showed that the results converge most of the time, and meshing has the most negligible effect in the current model analysis. Surprisingly, the current design has improved 87.5% of Torque and 87.9% of Cp from the baseline model. In employing the twisted centreline design, the force fluctuations are observed to be less significant, which may result in more life span of the turbine. The outputs obtained from this study postulates a better and simple VAWT design for the surroundings that have relatively less wind speeds, like the urban areas and rural living zones.

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