本研究以實驗方式探討低展弦比機翼產生之翼尖渦流的發展特性，並研究不同位置下前方機翼產生之尾流對尾隨機翼氣動力特性及流場結構的影響。本實驗使用的翼剖面為NACA0012，展弦比為4的有限長矩形翼為前翼，並將其作為渦流產生機翼。尾隨機翼模型同樣使用NACA0012為翼剖面，展弦比為6。實驗風速維持在9.74m/s，雷諾數則固定為1.0×105。為了研究前方機翼產生之翼尖渦的特性及分布情形，使用X型熱線測速儀測得流線方向及垂直方向的瞬時速度，以觀察前方機翼攻角分別為5°、10°及15°時產生之下洗尾流及翼尖渦流的結構及發展情形，並經由資料分析設定後方機翼的相對位置以架設模型，再使用力平衡儀測量後方機翼在受到不同程度之流場干擾下產生之力的動態響應及變化量。隨著尾隨機翼的位置改變，翼尖渦流對其所造成的影響同樣產生變化。根據實驗結果，翼尖渦流流過後方機翼時造成升力的增加或降低，而當後方機翼正好位於前方機翼之正後方(縱向距離為0)時，阻力會明顯增加，由此可印證飛機飛進機尾亂流區會造成飛機姿態劇烈改變的觀點。

This thesis has completed the study of aerodynamic properties and flow structures of two wings in tandem arrangement, including the experiments of force measurement, velocity measurements, and the power spectral analysis to investigate the flow structures and their development of trailing vortices. The wingtip vortices generated from the front wing is investigated from the streamwise velocity ratio contours and turbulent intensity. The results show that the tip vortex dissipates and spreads outside after passing the position of X/C=5. According to the results of power spectral analysis, the shedding frequency maintains approximately the same value for X/C=2 to X/C=4 with the angle of attack of 5° to 10° (i.e., before the front wing being stall), with the distance of the two wings are fixed. From the aerodynamic performance and coherent flow structure of the following wing, the impingement of tip vortices or wake generated from the front wing indeed drastically affect the following wing. The following wing shows a thin-airfoil stall without the obvious flow interaction from the front wing. However, the lift coefficient and drag coefficients were affected by the flow interaction from upstream.

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