國防科技在各個領域的發展一直是各國不可忽視的課題，其中能否掌握制空權往往是定奪戰爭成敗的關鍵，戰機性能的優劣自然地成為眾所矚目的焦點，近來五代機為追求高機動性故採用靜不穩定為理念進行設計，而靜不穩定造成戰機不易平飛的現象將由控制面來進行配平。時至今日，公認的五代機有美國的F-22與F-35、俄國的SU-57、中國的J-20與FC-31等戰機，得知各國正如火如荼地鑽研五代機的情形下，我國「國機國造」之政策亦著手實行，可國內缺乏控制面具偏轉角的情形下對五代戰機所造成影響之相關數據，故本研究將針對F-22的襟翼與升降舵進行偏轉，觀察這些控制面在偏轉後究竟會對戰機的升力、俯仰力矩以及流場產生多少變化。
研究中採用CFD(Computational Fluid Dynamics)計算流體力學方法來模擬F-22於0.6馬赫時，搭配不同攻角、襟翼與升降舵偏轉角所造成的影響，過程中使用了RANS(Reynolds-averaged Navier-Stokes equation)雷諾平均納維-斯托克斯方程，再搭配SST k-ω紊流模型來進行模擬，並將網格以六面體進行節點劃分。
本研究在F-22的模擬結果中表明，襟翼和升降舵的偏轉將會對F-22升力、升阻比及俯仰力矩產生一定影響力，同時也會使周圍流場發生變化，其中襟翼對俯仰力矩的影響不及升降舵，低攻角下兩者同時偏轉對升力及升阻比明顯有提高的作用，但本研究所使用之升降舵偏轉角度過大，導致低頭力矩過於強烈，另外值得注意的是，偏轉襟翼改變了下游流場，進而使升降舵升力下滑且在其外緣產生渦流。

關鍵字:CFD模擬、氣動力學、襟翼、升降舵、F-22

The development of defense technology in various fields has always been an important for a modern country, among which the ability to control air supremacy is often the key to win a war. Fighter jet performance is one of the crucial issues concerning national defense. The so called ‘fifth-generation” fighters are in pursuit of high maneuverability, so these jets were designed following the concept of static instability. However, static instability tends to prevent a jet to level off by trimming control surfaces. Therefore, to study the effects of control surfaces is very important for the design of these fighter jets.
Today, F-22, F-35, SU-57, J-20, and FC-31 are recognized as the fifth-generation fighters. Many countries are still in full swing to design their own fifth-generation fighter. In this study, the effects of control surfaces is studied via examining the effects of deflecting the flaps and elevators of the F-22. The objective is to understand to what extent the deflection of these control surfaces will change lift, pitch moment, and flow field of the fighter. Here, CFD (Computational Fluid Dynamics) method was used to simulate the effects of different angles of attack, flaps, and elevators deflections of the F-22 at Mach 0.6. This research uses RANS (Reynolds-averaged Navier- Stokes equation) and SST k-ω turbulence models to solve the flow field. The simulation uses unstructured hexahedral meshes to divide the nodes.
From the result, we can observe the effects of the deflection of flaps and elevators on lift, lift-to-drag ratio, and pitch moment of F-22, and also the changes to the surrounding flow field, among which the flaps have less effect on the pitch moment than the elevators.

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