拍撲翼面在陣風環境下之研究

以拍撲翼作為升力機制的微飛行器，現今已被廣用在軍事、救援、探勘等任務中，但是其飛行上的低高度、低速的飛行限制條件，造成抗風能力不足的現象，因此，探討低速陣風的影響已成為當前航空工業研究的重點。拜現今電腦技術快速發展所賜，透過增加網格數目來達到增加計算模擬的準確度，卻可以不增加運算時間。本研究首先以2D的拍撲翼面作為基準，將陣風的環境依照不同的方向、風速大小的變化與否做區分，再用動態網格的技術以Fluent這套軟體模擬出拍撲的動作。由我們的結果可以得到陣風環境會對上下翼面的渦流有很大的影響，更會直接影響拍撲翼的升力與阻力值，而陣風方向的不同影響更大。因此，本研究將會對拍撲翼面在陣風環境下性能分析有很大的幫助，更是未來研究微飛行器之抗風性的重要基石。關鍵詞：拍撲翼，陣風，動態網格，延遲失速

關鍵字

拍撲翼；陣風；動態網格；延遲失速

並列摘要

Micro Aerial Vehicles (MAV) use flapping wing as their flying mechanism. Nowadays MAV have been used more intensively in daily military, rescue, or reconnaissance missions, but their inherent nature of low altitude, low speed operation envelope will lead to their weak wind resistance ability, and thus the investigation of low level gust wind effect is becoming the focus point in recent aeronautical research. By the rapidly development in recent computer technology, we can improve simulation accuracy without using more time, through escalating the grid’s number. In this thesis, first choose a standard 2D flapping airfoil as a benchmark, then we can implementing gusty environment in several different directions, and simulate the wind amplitude with both constant speed and sine wave forms by using the dynamic grid technique of software Fluent to generate flapping motion. Our results show that the gusty environment has a strong effect on the vortices both on the upper and the lower surfaces, and will have direct influence on the lift and drag values of the flapping wing. But most profound effect is from the wind direction. As a result, this research will be very helpful to learn about the flapping airfoil’s aerodynamic performance in gusty environment, and could be an important cornerstone in the wind resistance capability consideration of future flapping MAV.

並列關鍵字

Flapping Wing ； Gust ； Dynamic Grid ； LEV

參考文獻

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[9] Jane Wang, Z., “Computation of Insect Hovering,” Mathematical Methods in The Applied Sciences Math. Meth. Appl. Sci. Vol. 24, 2001, pp. 1515–1521.

[12] Kim, T. U. and Hwang, I. H., “Reliability Analysis of Composite Wing Subjected to Gust Loads,” Composite Structures, Vol. 66, 2004, pp. 527-531.

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拍撲翼面在陣風環境下之研究

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