本研究以探討開縫翼端對渦流的影響為研究動機，以開縫翼端帆作為實驗模型，研究開縫翼端帆對於其後方之翼端渦流造成的影響。從熱線測速儀量測結果可以得到，通過狹縫的流會在翼端渦流外緣形成額外的自由剪切層，周圍造成更多的動量交換。
本研究中對兩種具有狹縫的翼端帆模型進行實驗與模擬，並與無狹縫的模型進行對比。從流場可視化的結果可以觀察到， 通過狹縫的流確實與翼尖渦流會產生交互作用。在6度攻角時，通過開縫翼端帆與狹縫翼端帆的流體會抑制翼尖渦流邊緣的擾動，但因為額外的自由剪切層影響，以及渦流本身的不穩定性，使得動量的傳遞更為劇烈，這對於加速渦流消散是具有潛力的。而在12度攻角下，通過狹縫的流體會在狹縫開口處形成一尺度較小的渦旋，此時除了狹縫本身的自由噴流與翼 渦流有交互作用以外，由狹縫產生的渦流也與翼尖渦流有對流的情形。
利用電腦進行穩態模擬分析，可以對流場的特徵進行猜測，並提供量測的參考。其結果顯示電腦模擬對通過狹縫的流體所產生的大部分的特徵皆有預測到，包含翼尖渦流的捲起以及通過狹縫流體所產生的渦。不過，於此渦流為極不穩定的現象，因此對於渦流產生的位置以及模型後方的速度場的量值分布的準確度可能較沒有那麼高，故電腦模擬僅作為實驗進行前的參考。
藉由熱線測速儀的量測，可以看到有狹縫兩種模型的方位角速度皆比沒有開縫的模型小，其中以開縫翼端帆的減幅較為顯著。而具有狹縫的模型後方的速度擾動雖然比沒有狹縫的模型小，但雷諾剪應力量值卻比沒有翼端帆的模型還要大，說明雖然擾動不強，但動量交換較劇烈。此結果也有利於渦流的消散。

In this study, two slotted winglet models are experimented, simulated, and compared with the model without slits (solid winglet). From the results of flow visualization, it can be observed that the flow through the slots does interact with the wingtip vortex. At an angle of attack of 6 degrees, the flow through the slotted winglet and the converging slotted winglet (nozzle slot winglet) suppresses the disturbances at rear of the model, but the additional free shear layer involved and the inherent instability of the wingtip vortex make the momentum transfer more intense, which has potential to accelerate the dissipation of the vortex. The azimuthal velocities of both slotted wingtip model are smaller than solid winglet in the hotwire experiment, especially for the slotted winglet. Although the turbulent intensity behind the slotted winglet model is lower than the solid winglet, the value of the Reynolds shear stress is larger than that of the solid winglet, which suggested that the momentum exchange is more intense. This result also favors the dissipation of the vortex.

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