研究鈍形體（Bluff body）的流場現象一直是流體力學和空氣動力學領域中的重要課題。透過研究鈍形體的流場現象和特性研究，可以了解流體在鈍形體周圍的流動模式、壓力分佈以及阻力生成的機制。這不僅有助於解釋各種實際流體問題，還為工程設計的優化提供了重要依據，有助於預測和控制流體力學效應，例如減少阻力、提高能源效益，以及改善風力發電設施和空氣動力載具的設計。
本研究針對三維軸對稱淚滴型鈍形體模型(Teardrop 40, T40)於低速水槽以及風洞進行流場可視化實驗，模型使用厚度比40% 的淚滴型幾何圖形軸對稱旋轉製成，討論T40模型於水槽低雷諾數下染液法和點墨法視流實驗的渦流結構與表面流動拓撲，以及於風洞較高雷諾數範圍進行油膜流場可視化實驗，觀察雷諾數對於流場分離、再接觸位置造成之影響，並且於風洞進行表面壓力訊號量測實驗，探討流場特徵與表面壓力之間的關係。
於低速水槽流場可視化結果發現，三維軸對稱T40模型於低雷諾數下會於模型兩側x/c = 0.28至0.44之間發生垂直渦旋分離，並出現渦流溢放結構和尾流結構，利用點墨法觀察瞬時表面摩擦線移動軌跡，繪製出低雷諾數1.77×10^4時的表面拓撲圖，且於拓撲圖中標明節點(N)、鞍點(S)和焦點(F)位置。
另外，使用開放式風洞進行油膜可視化實驗，於T40模型x/c = 0.2至0.28位置發現一小尺度的環狀分離泡結構，同時在雷諾數8.73×10^4時，開始於x/c = 0.44位置上觀察到紊流再接觸，此紊流再接觸隨雷諾數增加，具有不同方向角上的位置間歇性。利用平均壓力係數與擾動壓力係數驗證，紊流再接觸位置間歇性現象開始發生的雷諾數與油膜可視化中觀察到相同。

In this study, we focused on the phenomenon of flow over an axisymmetric body of a teardrop shape. This model named T40 is featured with a maximum thickness of 60mm, which is 40% of its chord length, 150mm. For the model at zero angle of attack, dye injection and ink-dot flow visualization experiments were conducted at a Reynolds number of 1.77×104 in a low-speed water channel to observe vortex structures and surface flow topology around the T40 model. Oil film visualization experiments were carried out in a wind tunnel over a Reynolds number range of 7.51×104 to 2.15×105 to observe the effects of Reynolds number on flow separation and reattachment positions. Surface pressure signal measurements were also conducted in the wind tunnel to investigate the relationship between flow characteristics and surface pressure.

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