在高攻角飛行時產生大規模的分離，因此其空氣動力特性明顯地受分離流主宰；分離流最顯著的特性是非定常的，常伴隨著大尺度的渦流發展，且在不同位置產生的渦流會互相干擾，整體流場的物理現象相當複雜。
本研究在一循環水槽中進行，使用視流觀察翼面上方渦流結構發展，與使用粒子影像測速儀測量取流場速度分布。以視流方法觀察不同實驗模型在攻角5°≦ α ≦30°的流場結構在高攻角的情況下，翼前緣產生分離渦流在翼面潰散且翼面出現螺旋式三維分離。量測翼面上方流場的速度值變化，進一步了解在高攻角三角翼流場結構的差異。
實驗工作將進行三角翼與NASA TP-1803及J31實驗模型之視流實驗，包括染液噴注法與表面水彩點墨法觀察渦流結構與潰散位置，並搭配粒子影像測速技術確認各項流場結構量化數據，包括速度向量、速度剖面、渦度等分布，確認不同位置產生的渦漩潰散位置，探討渦流之間相互作用對流場的影響。

For flow over a delta wing, a massive flow separation occurs at high angles of attack. In such a case, the aerodynamic characteristics are evidently dominated by the separated flows. One of the most significant characteristics of the separated flows is the unsteady phenomenon, which is accompanied with the development of large-scaled vortical flows. Moreover, the vortices generated at the leading edges may interfere with each other. The present experiment was carried out in a recirculating-type water channel. The characteristics of the vortex flow developed above a delta wing model were studied by means of flow visualization. The angles of attack (α) of the delta wing model were in a range of 5°≦α≦ 30°, respectively. Particular attention was paid to the flow conditions under which the event of vortex breakdown took place. The corresponding limiting-streamline patterns appeared on the surface of the delta wing model were of interest to study. Further experiment was carried out with a NASA TP-1803 model and J31 model. The dye injection method and the surface dot paint method were employed to unveil the vortex structure and the location of vortex breakdown associated with this model. The PIV flow visualization technique was employed to observe local characteristics around the testing models. Consequently, discussion of the experimental findings with respect to the flow parameters of α was carried out. The impact due to the interaction between the vortices developed above this model is addressed in this report.

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