俯仰動作對仿燕尾蝶型拍撲翼氣動力之數值模擬

A Preliminary Study of the Aerodynamic Force Revolutions induced by Butterfly's Flapping Wings in pitching motions

黃兆廷(Jau-Ting Huang)

指導教授 ： 牛仰堯

共同指導教授 ： 湯敬民(Jing-Min Tang)

淡江大學/工學院/航空太空工程學系碩士班/碩士(2013年)

https://doi.org/10.6846/TKU.2013.00157

摘要

進行蝴蝶模擬前進飛行時非均勻流對於其氣動力改變分析，阻力係數部分，正攻角下拍行程係數值為正、上拍行程為負，負攻角下拍行程係數值為負、上拍行程為正；升力係數部分，下拍行程攻角為正時，有助於提高升力，上拍行程攻角為負時，升力係數有最小值；俯仰力矩係數部分，在下拍行程時會造成一個使蝴蝶抬頭的力，當在下拍行程一個正的攻角，會使蝴蝶擁有更大抬頭的力，於上拍行程時會造成蝴蝶一個抬尾的力，當遇到負攻角時會使抬尾的力增大。
　　身體主動俯仰動作的模擬部分，升力與俯仰力矩與身體兩個俯仰角度之間差別不大，只對阻力係數變化有關，對此推測身體俯仰對於向前飛行時的推力有幫助。而流體經過身體主動俯仰飛行中的蝴蝶時，身體俯仰會造成翅膀上的壓力分佈有所改變。

關鍵字

蝶型拍撲翼 ； 計算流體力學 ； 微飛行器

並列摘要

Aerodynamic simulation of Butterfly’s flapping wings in non-uniform flows is performed. In the prediction of the aerodynamic forces, the drag coefficient is shown to be positive when the angle of attack is positive during the downstroke. However, the drag coefficient is shown to be negative during the upstroke. Also, the drag coefficient is negative when the angle of attack is negative during the downstroke., but the drag coefficient is positive during the upstroke ; For lift coefficient, the lift is enhanced during the up-stroke and reaches its minimum when angle of attack is positive. For moment coefficient, the pitching up force in the downstroke is produced. If angle of attack is positive, the pitching moment is enforced. However, the moment of the pitching-down appears and is enhanced when the angle of attack is reduced in the upstroke.
　　In our simulation Butterfly pitching body in forward flight, the distributions of the lift and moment coefficients are still same in the case without the body motion of pitching except the distribution of the drag coefficient. This combined the body motion of pitching with flapping motion is shown to strengthen the thrust during the forward flight of the butterfly.

並列關鍵字

butterfly-type flapping wing ； CFD ； MAVs

參考文獻

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