直至現今自由車發展已成熟，對於勝利分秒之差，如何提升效率與降低阻力是近年來各國不斷努力的目標，甚至使用風洞來量測風阻的變化，以協助減阻之相關研究，而對比國內風洞試驗主要都是以建築、航空太空、火箭、汽車為主，截至目前為止還尚未有真人與全尺寸模型運動相關的風洞測試，本研究主旨在於建立自由車選手風洞實驗之能量，分析選手數據並將數據進行國內外比對，同時進行減阻衣之相關研發。
本研究總共包含四次風洞實驗，兩次車手模型實驗與兩次真人實驗，車手模型實驗主要是配合減阻衣之相關研發，也同時從中了解表面流場結構；而真人選手實驗主要是探討姿勢與踩踏對阻力之影響。
車手模型實驗是採用全尺寸車手模型姿勢為下彎把(Dropped position)，踩踏角以左腳定義為18度，並將自製的10種不同表面粗糙元貼於手臂、肩膀、腰部與大腿，而風洞實驗證明了，使用表面粗糙元於模型的兩肩、上臂、腰部與大腿，可以達到延後分離的效果，進而達到減阻之目的，特別是於本實驗中高雷諾數的部份，其中表面粗糙元3 (Pattern3)的阻力係數可以比原先模型降低超過6%，爾後將此圖形與自由車車衣結合，配合衣服的粗糙度與表面粗糙元進行實驗。
從模型穿著車衣實驗中發現，3R在手臂與肩膀可以採用較粗糙的直條布或是蜂巢布，腰部則是粗糙的蜂巢布，背部可採用較光滑的布料，此組合在本研究中效果佳，再配合表面粗糙元3測試結果，發現3RT得到效果最佳，尤其是在腰部上，效果最為顯著，甚至可以達到減阻7.5%，但是若太過於粗糙可能會形成反效果，故表面粗糙元與衣服的粗糙度須適當的做調配，另外，本研究中證實了人體模型穿著不同的衣服下，達臨界雷諾數時，阻力驟降現象是有可能產生於車手模型穿衣實驗中，而在穿著衣服的情況下，手臂側邊有可能會產生分離泡，延後最後分離點位置。
本研究中在真人選手靜態實驗中，使用不同的姿勢所量測到的阻力面積與阻力係數，對比國外的文獻無太大差異，都在合理範圍內，因此未來可以提供國內外更多自由車相關研究。而在真人選手踩踏實驗中，選手踩踏習性與量測到力量息息相關，因此每個人踩出來的波型也會因人而異，當選手用力踩踏時，量測到的阻力為負值，未來若是想要精進選手訓練，必須要以每位選手的特性去做調整。

When wind flows over a human body, it may cause flow separation on the body surface. Therefore, a wake region is formed behind the body. The main source of drag is the difference between the pressure before and after the body called the pressure drag. The aim of this study is to change the surface roughness of the full-scale cyclist model in dropped position to achieve drag reduction. Roughness patterns and cycling jerseys were used to delay the separation lines in wind tunnel experiment. For the best case, the drag reduction is amounted to 6.7 % in the roughness patterns experiment and 7.5% in the cycling jersey experiment, compared to the CD value of the reference case with no roughness pattern and cycling jersey at the same Reynolds number. Surface pressure readings were taken during the drag measurement to increase insight in drag reduction mechanisms. The drag crisis may occur on cyclist model with cycling jerseys and separation bubble may be on the arm. Finally, the roughness patterns and cycling jerseys were worn and tested by Taiwanese cyclists to explores the effects of different postures and pedaling speeds on drag.

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