結合實驗與數值方法研析噴流式Gurney式襟翼應用在無人飛機時之空氣動力特性

Experimental and Numerical Investigation on the Aerodynamic Characteristics of Combined Jet and Gurney Flap

黃俊瑋(Jyun-Wei Huang)

指導教授 ： 鄭仁杰

國立虎尾科技大學/工程學院/航空與電子科技研究所/碩士(2012年)

https://doi.org/10.6827/NFU.2012.00135

摘要

無人飛行器(UAV)具有低成本、高機動性及避免人員損失風險的優點，是各國發展之重點，為了增加UAV之性能，發展非傳統型的高升力及操控面的設計，在維持飛機的氣動力特性考量下，以減少結構重量，達到增加滯空時間。本研究結合數值模擬與實驗量測方法相互驗證，有系統的探討Gurney Flap、Jet Flap及整合兩者特點所研發出噴流式Gurney Flap之流場與氣動力特性。在數值方面本文在二維與三維紊流流場下，當Re = 3×106及M∞ = 0.2時，探討Gurney Flap、具槽孔之Gurney Flap、T-Strip、Jet Flap與結合Jet 與Gurney Flap應用機翼等各項參數對流體結構與氣動力特性與隱匿性的影響。在實驗方面，利用風洞進行機翼裝設Gurney Flap的升阻力量測，比較實驗數據與數值模擬結果，發現其相對誤差介於10-20%。

二維結果顯示，在Gurney Flap方面，改變0.5≦Lh≦4%、0≦Sf≦10%、0°≦θf≦180°，Cl可以提升115.4%。在Jet Flap方面，改變0.005≦Cμ≦0.02、0≦Sj≦10%、0°≦θj≦180°， Cl可以提升165.5%。在具槽孔之Gurney Flap方面，改變0≦Nh≦3，當Nh =1時，Cl提升1.63%、Cd減少16.87%。T-Strip方面，隨著Flap高度增加，升力曲線斜率與最大升力係數也會隨之變大，但阻力增加的趨勢更大。在結合Jet與Gurney Flap方面，改變相對關係之位置，當噴流位於Gurney Flap正下方時，有較大升力。而適當的Gurney Flap 高度及噴流強度的結合，在相同的氣動力性能要求下，可以降低只用Gurney Flap時阻力及只用Jet Flap時所需供給之能量。
三維結果顯示，在Gurney Flap方面，改變0.5≦Lh≦4%、0≦Rf≦1、不同安裝位置，CL以提升109.89%。在具槽孔之Gurney Flap方面，改變0≦Nh≦3、0≦Rf≦1，當Nh =1時，CL升1.54%、CD少6.31%。在Jet Flap方面，改變0.005≦Cμ≦0.02、0≦Rj≦1、不同安裝位置， CL以提升159.4%。在結合Jet與Gurney Flap方面，改變相對關係之位置，不同相對位置對機翼之影響與二維結果相近。
RCS結果顯示，在翼後緣裝設Gurney Flap時，結果相對未裝flap沒有明顯的差異，相對裝設傳統型Flap明顯減少。

本研究探討噴流式Gurney Flap之效能，在非傳統Flap前提下設計與規劃，尋求理想的高升力模式。建立各參數與提高升力效能的相關性，解析現象形成原因與物理機制，對系統設計提出工程的關切點，作為設計準則的參考。

關鍵字

無人飛行器 ； Gurney型襟翼 ； 噴流 ； 空氣動力

並列摘要

Unmanned aerial vehicle (UAV) coupled with comparatively low cost and flexibility, makes this type of vehicle extremely attractive. The movable high lift device and control surfaces are instead by this jet type Gurney flap for the purpose of reducing the weight and power requirement. The numerical simulation and experimental measurement is investigate the aerodynamic characteristics of jet type Gurney flap, which is developed coupling with the advantages of Gurney flap and jet flap, applied on the UAV. The effects of the configuration parameters, installation arrangement, and operation mode of this jet type Gurney flap on the wing under different flight conditions will be discussed in detail for the flow structure, aerodynamic, control and stealth properties. In experiments wind tunnel investigation was undertaken to effects of Gurney flap on a wing, the result of life and drag between the experimental and numerical simulation is in the range 10-20%.
This research utilizes 2D and 3D turbulent numerical simulation to study aerodynamic characteristics of a Gurney flap, jet flap, perforate Gurney flap, T-strip and combined jet and Gurney flap on a NACA 4412 airfoil at Re = 3×106 and M∞ = 0.2. The 2D results show the lift is increase as the flap height is increase for the Gurney flap, the maximum enhancement of the Cl is 174.3% as 0.5≦Lh≦4%, 0≦Sf≦10% and 0°≦θf≦180°. For the jet flap, the maximum enhancement of the Cl is 165.5% as 0.005≦Cμ≦0.02, 0≦Sj≦10% and 0°≦θj≦180°. For the perforate Gurney flap, the maximum enhancement of the Cl is 1.63% and the maximum decrease of the Cd is 16.87% as 0≦Nh≦3. For the T-Strip, the lift curve slope and maximum Cl is increase with flap height. However, the drag is also growth apparently. For the combined jet and Gurney flap, the case of a jet flow just under Gurney flap has the best lift coefficient. Besides, it is found that a proper combination of flap height and jet flow momentum can reduce the drag for the case of Gurney flap and the energy supply for the case of Jet flap under the similar aerodynamic requirement. The 3D results show the lift is increase as the flap height is increase for the Gurney flap, the maximum enhancement of the Cl is 109.89% as 0.5≦Lh≦4%, 0≦Rf≦1 and different installed position. For the perforate Gurney flap, the maximum enhancement of the Cl is 1.54% and the maximum decrease of the Cd is 6.31% as 0≦Rf≦1 and 0≦Nh≦3. For the jet flap, the maximum enhancement of the Cl is 159.4% as 0.005≦Cμ≦0.02, 0≦Rj≦1 and different installed position. For the combined jet and Gurney flap, change the relation position, the effect of the different relation position upon the plane wing is as similar as 2D result.
The RCS results show the installation of the Gurney flap at the trailing edge, no significant difference relative no flap and reduced relative the installation of the traditional flap.
The correlation for the practical design parameters with the jet and Gurney flap performances is established. This study also investigates the physical mechanism of high lift applied on the wing. The key points regarding the UAV system design and environment control can be provided the future reference for engineers designing such a system.

並列關鍵字

UAV ； Gurney Flap ； Jet Flow ； Aerodynamics

參考文獻

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