本研究透過風洞實驗，針對透孔率50%之透孔盤模型於均勻流與邊界層流中進行尾流逐點量測，透過改變模型與來流之偏向角，分析其速度分布、紊流強度、動量通量、紊流積分尺度等氣動力特性，利用所量測之風速去計算簡化後之紊流動量方程式中各項之值，並探討在不同邊界層厚度與透孔盤模型寬度比例(δ⁄D=4.5與3)所造成之尾流特性及發展情況，兩種透孔盤模型可視為模擬葉面直徑66.7公尺和100公尺的風機於大氣邊界層下之實驗結果，並將這些結果與均勻來流情況做比較。
本研究量測與計算在均勻來流環境中且模型正向於來流時之推力係數，驗證動量理論及圓盤理論所計算之推力係數與六力平衡儀所量測結果之差異。利用圓盤理論取尾流最高平均速度降所計算之推力係數為0.678，動量理論所計算之推力係數為0.645，而六力平衡儀所量測之推力係數為0.596。表示透過量測尾流風速剖面利用動量理論去計算透孔盤模型推力是可行的，但是量測尾流剖面最低平均速度利用圓盤理論去計算透孔盤模型推力的誤差會較大。
本研究探討在不同邊界層厚度與透孔盤模型寬度比例(δ⁄D=4.5與3)所造成之尾流特性及發展情況，分析尾流的氣動力特徵分布發現邊界層效應對風機尾流的影響很大，對於後方尾流內外動量的混合與損失速度的回復有極大的幫助。觀察透孔盤模型尾流無因次速度降水平分布，在δ⁄D=4.5與3時的尾流最高無因次速度降低量分別為0.35與0.38，代表δ⁄D越大會使速度降低量越少，又由於模型的推力係數與尾流速度降成正比，表示在模型δ⁄D越大的情況下相同透孔率的模型推力係數會越低，另外在均勻來流實驗下空氣流過模型後的最高無因次速度降低量為0.46，證明邊界層效應會降低模型尾流的速度降低量。
透過改變模型與來流之偏向角，發現在均勻流環境下不同偏向角時的尾流寬度完全由透孔盤模型的投影寬度來決定，尾流的寬度會隨著下游距離而線性增加，在X/D=1與4時，尾流寬度約為1.14倍與1.19倍的透孔盤投影寬度。在邊界層來流的環境下，尾流的寬度也會隨著下游距離而線性增加，但偏向角的上升也會使尾流寬度下降，與均勻來流時的實驗結果不一樣，不同偏向角時的無因次尾流寬度並沒有完全一致，尾流寬度而是與模型的偏向角成正相關，偏向角越大尾流寬度也越大。
由模型中心對稱軸(Y=0)之正後方尾流的速度分布，可以計算出紊流動量方程式中各項之值，發現在邊界層環境下主導尾流動量傳遞的項為U ∂U/∂x與-∂/∂z ((u^' w^' ) ̅ )，相較之下其他項之值都很小，尤其是黏滯應力項幾乎沒有影響力，表示平均流向速度之改變(U ∂U/∂x)主要是受動量通量之縱向改變(∂/∂z ((u^' w^' ) ̅ ))所影響。

The problem of the interaction between atmospheric boundary layer and wind turbine wakes arises with the development of offshore wind farms. Compared to the inflow, wind turbine wake has lower velocity and higher turbulence intensity, it make the power production decreasing and the fatigue loading increasing. The porous disks, based on the concept of the actuator disk theory, are employed for studying the characteristics of wind turbine wake some distance downstream. This paper examines experimentally the wake characteristics of a porosity 50% porous disc model in a uniform free stream and turbulent boundary layers. Hot-wire velocity measurements were carried out in the wake region. This paper also use force balance to measure thrust of the model. The results show the wake with higher ratio of boundary layer thickness and porous disc diameter have lower velocity deficit, added turbulence intensity and distance to recovery. The thrust coefficient of porous disc model obtained by actuator disc theory, momentum theory, and force balance respectively are 0.678, 0.645, and 0.596. U ∂U/∂x, W ∂U/∂z and -∂/∂z ((u^' w^' ) ̅ ) are the main factor to influence wake momentum transfer in vertical distribution.

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