本研究針對均勻來流流經自行車手所產生之尾流結構進行探討，當中所採用之車手模型為1/5縮尺比例以及Hoods position騎乘姿勢，而踩踏角為195° 也使得兩側大腿於對稱的位置，使得尾流形狀也較為對稱。過程中透過尾流量測實驗，並結合多種不同的流場可視化技術，以期能夠對一些流場結構能有更為詳細的描述。
由實驗結果發現自行車手的臀部周遭具有較大的速度缺陷，這合理的推測該處對於空氣動力阻力具有顯著的貢獻，並能夠與附近所發現的大尺度連貫結構做一些相關連結。不過由流場可視化的結果也指出由頸部與肩部之結合處所形成之二次流將發展成一對稱渦流對，雖然於下游的尾流量測結果已無法清楚分辨出該結構，不過由速度缺陷的形狀也能夠說明此渦流對對於空氣動力阻力的貢獻亦不容小覷。
另外，尾流量測的結果也幫助說明了左右大、小腿間夾角的不同造成兩側三維性程度的不同，這與大型流場結構的發展程度息息相關，且紊流之高階統計量也能幫助尾流範圍的界定。

In this study, we explored the flow characteristics and aerodynamic performance concerning a 1/5 scale model of a cyclist at the hoods position. Complementary to each other, the wake measurements and flow visualization results obtained enable us to discuss the flow around the model and the wake flow structures in detail. Experiments were conducted in a water channel and a low-speed wind tunnel, respectively. In the water channel experiments, the Reynolds numbers based on the torso length of the model was 1.1×10^4; on the other hand, in the wind tunnel experiment, the Reynolds numbers was 6.5×10^4. In the water channel, flow visualization was made with dye injection from the outside of the model and dotted paint applied on the model surface; in addition, PIV measurements were carried out in the reverse flow region of the wake. In the wind tunnel, two methods were employed, namely, the flow visualization experiment was made by applying oil-film on the model surface and the hot-wire measurements were conducted in the wake region.

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