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- 學位論文
提高拍翼升力之單向閥門製作
Fabrication of Check Valves on Flapping Wings for Lift Enhancement
摘要
本篇論文提供一個新型的翼膜設計概念，即針對舊式的PET翼膜安裝單向閥門(check valve)，使其在拍翼機進行拍翼的過程中，藉由單向閥門於拍翼上行程時開啟閥門，而下行程時關閉閥門的開合控制降低翼膜所需承受的空氣阻力，而達到提升拍翼升力的目的。文章中也會提及各式的加工技巧以及軟體操作概念輔助，進行諸如機構設計以及結構、自然頻率分析等，所使用的軟體包括Solidworks和ANSYS，其中Solidworks主要輔助機構以及單向閥門結構設計，而ANSYS軟體則是用於單向閥門在拍翼運動中之自然頻率模擬量測，藉由頻率響應之計算與分析來確保閥門的設計在翼膜上運作之實用性以及可靠性，本論文最終所設計之單向閥門，經過自然頻率分析所得到之結果為17.86Hz，以低通濾波的概念來說明，其成功達到所期望之高於拍翼頻率(14Hz)的範圍，從而認定此單向閥門之設計是可行的。此外本論文也提及到運用傳統加工的方式如切割機的運作，輔助製作單向閥門。 風洞實驗在本篇論文中的主要目的是比較翼膜在有無安裝單向閥門間之升力差異，以便做進一步的單向閥門設計與校正。本研究最終目的為研發出能夠藉由降低拍翼阻力來達到提升平均拍翼升力之單向閥門，並以20cm翼展之「金探子」PET拍翼膜為例，在加裝半徑7.43mm之三樑式單向閥門後，在3.7V電壓，傾斜角30度，自由流速3.0m/s下，輸出平均升力25.5gf，高於無安裝單向閥門拍翼平均升力86%。
並列摘要
This thesis provides the new concept, which is related to the wing membrane where some check valves were attached on the wing membrane, which acts as an actuator. The opening and closing of check valves will help in reducing the air resistance of the wing during the upstroke, which can improve in the overall lift during the flapping. This article also demonstrates the various processing technique and software processing like mechanism design, flow field analysis, and more. The software which made in use was Solidworks and ANSYS where Solidworks was used primarily for design and development of various structure like check valve structure design, and more and ANSYS was used for the analysis of natural frequency on the wing membrane during to flapping process in order to facilitate the availability of check valves design on the wing membrane. The result of natural frequency comes to 17.86Hz, which is in anticipation of the range that higher than flapping frequency (14Hz) by frequency response analysis. As the conception of low-pass filter, it is easy to quantify the effect of check valves on flapping. In this study, it also mentions the traditional processing methods like the operation of cutting machine-auxiliary production of check valve. The wind tunnel experiment was conducted where the comparison was made with and without the check valves. Furthermore, wing design calibration has also been conducted. The final objective for this experiment was to develop a check valve that can increase the overall lift by reducing the wind resistance during the upstroke. For the current study, Evans mechanism was used with 20cm wingspan of PET as the wing membrane the check valve with three beams of radius 7.43mm was used which get active during the downstroke. At 3.7V with 30 inclined angle at 30(m/s) wind velocity the average output of lift was 25.5(gf) which is 86% higher than the valve less model.