無人戰鬥飛行載具（UCAV）是現代空中優勢的重要發展項目，它在要求隱身性能的同時，也須具備良好的操縱性和飛行表現。仿NATO開發之通用無人飛行載具SACCON（Stability and Control Configuration）的UCAV NCKU model，研究其多重渦流結構對理解無人飛行載具的空氣動力學有很大的幫助
在本研究中，將螢光染料塗抹在UCAV NCKU model上，將渦流可視化，並結合表面壓力進行分析。可視化結果清楚顯示，在高雷諾數時，機身與翼身交界處的inner vortex沒有形成跡象。tip vortex在低攻角形成後，隨著攻角的提升向apex遷移，過程中迅速地佔據翼身鈍形翼前緣的接觸流區。apex vortex與tip vortex在合併時的共渦面現象在可視化實驗中也有所觀察。UCAV NCKU model模型的鈍形翼前緣與機身厚度的設計使得流場對雷諾數敏感，這也是本研究欲深入探討的重點。

Unmanned Combat Aerial Vehicles (UCAVs) are critical for achieving modern air superiority, requiring both excellent stealth capabilities and superior maneuverability and flight performance. UCAV NCKU Model imitating NATO's General Unmanned Aerial Vehicle SACCON (Stability and Control Configuration) and studying its complex vortex structures significantly enhances our understanding of the aerodynamics of spanwise-varying leading edge configuration UCAV model.
In this study, oil-film was applied to the UCAV NCKU model to visualize the vortices, and surface pressure analysis was conducted. The visualization results showed that after the tip vortex forms at low angles of attack, it shifts towards the apex as the angle of attack increases, easily occupying the attached flow area at the blunt leading-edge wing. The common vortex sheet phenomena during the merging of the apex vortex and tip vortex were also observed in the visualization experiments.
The surface pressure measurement and 2D force measurement experiment also provide quantitative validation to the vortex development.

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