一般飛機的雷諾數約為百萬級別，但無人飛行載具和無人戰鬥飛行載具因為尺寸的限制及任務的需求不同，因此雷諾數會較一般民航機低1~2個數量級。隨著無人飛行載具的崛起，使得低雷諾數下的空氣動力特性越發重要。
本研究針對不同機翼幾何配置的戰機模型進行低速風洞的可視化流場實驗，使用的模型分別為前緣延伸面模型TP-1803及無輔助翼之TP-1803模型和無人戰鬥飛行載具SACCON模型，討論每個模型在靜態不同攻角下的渦流結構和其流場對於雷諾數的敏感程度，並且透過模型外型的差別來探討輔助翼渦漩與翼前緣幾何對流場的影響。同時，也會在TP-1803模型進行表面壓力量測實驗，探討渦漩潰散的訊號及其特徵。
從視流結果發現，無輔助翼之TP-1803模型在攻角20˚時翼面上已無渦漩存在，而有輔助翼之TP-1803模型在低攻角時主翼渦漩與輔助翼渦漩獨立存在，在攻角20˚發生交互作用，在攻角30˚輔助翼渦漩發生潰散，有輔助翼之TP-1803模型因主翼渦漩與輔助翼渦漩之間的交互作用，會使得失速攻角延後。SACCON模型的翼前緣幾何會隨著翼展而有所變化，因此導致流場更加複雜，此模型在攻角10˚時流場以附著流為主，在攻角15˚則以前沿渦漩為主要特徵。雷諾數的影響對銳形翼前緣的TP-1803模型來說主要是渦漩間的交互作用會因雷諾數增加而減弱，渦漩的二次分離線也會隨之往外移動，但潰散位置並不會隨雷諾數而改變；對於同時具有銳形和鈍形翼前緣的SACCON模型而言雷諾數的影響更為顯著，在低攻角下的分離位置隨雷諾數增加而延後，再接觸線則往前，翼面上小尺度的擾動也會隨之出現並且更加顯著，在高攻角下前沿渦漩向外側移動，渦漩潰散點依然無明顯變化。
另外，TP-1803模型的壓力訊號頻譜圖中在高攻角110 Hz附近出現的響應是由渦漩潰散尾流的螺旋不穩定造成，從互相關分析也發現當渦漩完全潰散後相關係數會急遽下降，壓力係數的回升與壓力係數方均根值的驟增亦可為渦漩潰散的特徵之一。

An experimental investigation of vortex structure on military aircraft models with different wing geometric configurations at different angle of attacks and Reynolds number is presented. The models are the leading edge extended surface model TP-1803, the TP-1803 model without strake wing, and the generic unmanned combat aerial vehicle model with 53˚ swept angle and lambda wing planform. Oil-film visualization method is used to obtain the limiting streamline of models. At low speed range, the Reynolds number between 4.11×10^4 to 1.2×10^5, the trajectory of vortex core position, vortex strength, vortex interaction, vortex breakdown has been observed. The results indicate that the effect of Reynolds number on the models can be significant, especially during the vortex interaction process and on the unmanned combat aerial vehicle model due to its complex leading-edge geometry.

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