本論文利用風洞實驗在低雷諾數下低展弦比機翼探討氣動力特性，氣動力特性包括升力、阻力、俯仰力矩係數、升阻比及誘導阻力。展弦比為1包含有翼弧之機翼乃在於比較厚度比效應及不同展弦比氣動力特性之研究，為了更深入探討低展弦比機翼翼尖渦流之流場結構，故利用低速煙洞探討二維翼切型流場結構變化與三維機翼翼尖渦流相互干擾及影響機翼表面程度做全盤性比較探討，展弦比為1有較明顯因升力而產生之誘導阻力並且所有展弦比為1的失速攻角皆超過20度攻角，實驗結果顯示升力曲線斜率、最小阻力、誘導阻力及升阻比，厚度較薄之機翼比厚度較厚之機翼為佳. 另外有翼弧機翼之升阻比有其較佳之結果，本論文亦針對飛機性能參數做討論，實驗結果與分析數據可以提供給從事微型無人飛行載具研究者一些設計之參考。

The thesis was intended to investigate the aerodynamic characteristics of low-aspect-ratio wings at low Reynolds numbers by experiments. The aerodynamic properties, including lift, drag, pitch-moment coefficients, lift-to-drag ratio and induced drag obtained. The effects of thickness ratio and camber were investigated. The aspect ratios of most wings tested in the experiments were 1. Wings of larger aspect ratios were also tested for comparison. In order to obtain more understanding about the structures of tip vortices, flow visualizations of 2-D and 3-D wings were conducted in a smoke tunnel. The lift due to tip vortices was obvious for wings of AR=1, and their stall angles were all larger than 200. The experimental results showed that wings of smaller thickness ratio were superior on the properties of lift-curve slope, minimum drag, induced drag, and lift-to-drag ratio. Cambered wings were recommended for their better behaviors on lift-to-drag ratio. Some aircraft performance parameters were discussed. The experimental results and analysis can provide the instructions and performance data for designs of MAVs.

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