隨着科技的進步與運動科學的發展，在專業級別的自由車競賽裡，如何提升空氣動力學特性尤其是自由車空氣動力減阻問題是近年來許多研究者所關心的議題，特別是騎乘者(自由車選手)的阻力。
本研究針對不同體態的自由車選手在不同姿勢下進行風洞實驗，討論影響風洞實驗數據品質的參數，比較自由車選手進行動態踩踏實驗與靜態實驗並且變換姿勢對阻力造成的影響、前期研究車衣搭配粗糙元在車手模型下阻力量測的結果和軀幹角度與前視投影面積的關係。
由實驗結果發現，自由車選手動態踩踏與靜態實驗時的阻力並非完全一致不建議量測靜態實驗完全取代踩踏時的實驗結果，第二發現在車手模型身上有減阻效果的車衣搭配粗糙元並非在每位選手身上均能造成減阻的效果，前期研究的車衣搭配租糙元是在參與的選手以及車手模型中是在高寬比1.4以上身材的選手才會產生減阻的效果。實驗也觀察出軀幹角度與其前視投影面積有高度的相關性。
另外，也探討了本研究所使用的風洞風速不確定度，風洞風速不確定度在本研究所使用的4個風洞扇葉轉速下都小於1%。最後進行縮尺自由車手側風風洞油膜實驗，觀察近表面流場，提供未來全尺寸風洞實驗，當作參考依據。

Nowadays, scientists are noticing the aerodynamics of cyclists and how to achieve drag reduction when cyclists riding bicycles. Especially the drag produce by cyclists’ bodies. This study aims to continue the former study testing the cycling jersey with roughness, which can reduce drag and happen drag crisis on the specific Reynolds number and happen on realist cyclist. Realist cyclists do not like the cyclist model in the former study they have different body shapes and postures even the angle of the postures. Therefore, doing realist cyclists wind tunnel experiment measure the drag with a different posture and different body shapes of cyclists is important. Additionally, cyclists will not always be riding straight to the wind also will encounter the crosswind effect. we do the flow visualization experiment on a 1/5 scale-down cyclist model to explore the surrounding flow field when it encounters the crosswind effect.

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