隨著定翼無人機外型流場設計發展到達相當的成熟度，對於日益困難的任務需求，針對各項任務內容專門研發創新構型設計是現今無人機設計工程師尋找突破的方法之一。本研究以翼展範圍為2至5公尺的低速低高度太陽能無人機作為設計發想，參考衝壓式降落傘的外型特點自行開發出第一款創新構型-Π式構型(又稱Π型翼)的原型機翼，透過結合田口式直交表實驗法(簡稱田口法)以及兩類計算流體力學(CFD)套裝軟體-OpenVSP以及Ansys Fluent建立一套研究流程；首先設計相同環境與操作條件下之簡易梯形翼，利用升力線理論計算其升力係數與阻力係數用以校正OpenVSP環境建立結果以及Ansys Fluent環境建立結果；接著在Π式構型的概念下設計原始Π型翼，並進行模擬分析，發現升力以及阻力尚不理想。利用田口法將升阻力係數分解成三項品質特性，並設置共八項控制因子，馬赫數作為干擾因子，使用L18直交表進行實驗與控制因子變異分析，再利用信賴區間的概念對數據分析的結果進行重複確認，最後得出之最佳組合的Π型翼。Π型翼設計相較於展弦比為10的梯形翼，雖然升阻比依然較低，然而在每單位翼面機飛機重量15(kgw/m^2)以下以飛行速度20(m/s)、攻角0度下巡航飛行時，太陽能儲存的功率最高可以增加至240%；運用田口法將原始Π型翼改良至最佳組合Π型翼，在展弦比降低的同時最大升阻比數值依然相當，並在攻角0度時最佳組合Π型翼的升力數值相較於原始Π型翼增加66%，奧斯瓦爾德效率因子增加36%，太陽能儲存的功率最高增加至57%。

In this research, a low-speed and low-altitude solar-plane with a wingspan of 2 to 5 meters is used as a design idea, and the first innovative configuration-the Π configuration is developed by referring to the appearance characteristics of ram-air parachute.
And we combine Taguchi method and two types of computational fluid dynamics (CFD) software - OpenVSP and Ansys Fluent to establish a step of research and improvement processes for wing design.
First we design a simple trapezoidal wing under the same operating conditions, and use Prandtl lifting-line theory to calculate its lift and drag coefficient to regulate OpenVSP environment and Ansys Fluent environment.
Next, established a model of the original Π-type wing under the preset conditions and the concept of the Π-type configuration, simulation analysis was performed. It is found that the lift and drag were not yet ideal.
Use Taguchi method to decompose the lift and drag coefficient into three quality characteristics, and set total of eight control factors. We also set Mach number as the interference factor. Use the L18 orthogonal table to conduct experiments and control factor variation analysis, and then use the concept of confidence interval to analyze the data.
In the end, compared with the trapezoidal wing with an aspect ratio of 10, Π-wing has a lower lift-to-drag ratio. However, when cruising and flying speed is 20(m/s), angle of attack is 0, power stored by the solar energy can be increased up to 240%.

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