本研究旨在探討俯仰率（Pitch rate, PR）與攻角範圍對Slingsby T-67 Firefly 飛機全機動態失速特性之影響。透過商用計算流體力學（CFD）套裝軟體進行數值模擬，數值方法使用URANS之k-ω SST紊流模型搭配γ-Reθ過渡模型計算，並運用滑移網格（sliding mesh）技術實現全機之動態俯仰運動。本論文探討了三種攻角範圍（5°至15°、5°至20°與5°至23°）及三種不同俯仰率（10°/s、15°/s及20°/s）對動態失速遲滯效應之影響，並分別找出每個案例的動態失速臨界攻角及最大升力係數，深入探討其伴隨的流場現象與氣動力影響，以上結果以升力、阻力及俯仰力矩係數對攻角圖、Q-criterion等值面與壁面剪應力（wall shear stress）來觀察並呈現。
靜態驗證計算結果與文獻的實驗數據於整體趨勢上具備高度一致性，驗證了本研究所採用之數值方法具有良好之可靠度。此外，研究結果明確指出過渡模型之關鍵作用：若未引入γ-Reθ過渡模型（transition model），數值解於低攻角便會提早發生失速分離；相較之下，採用γ-Reθ過渡模型能有效捕捉高攻角流場現象與氣動力特徵之預測準確度。基於全機靜態與動態失速之模擬分析，獲得以下結論：首先，擴展最大攻角極限之主要物理效應在於拉長全機於紊亂流場中之時間，原則上並不改變動態失速臨界攻角。惟在高俯仰率（PR=20°/s）操作下存在特例：強烈的動態遲滯效應將失速發生時機大幅推遲，若全機於動態失速完全發展前便達到最大攻角極限並轉入下俯行程，流場之演化將受運動行程之提前結束所影響，進而改變所觀測到之氣動力峰值特徵。
發現T-67全機於5°至15°攻角範圍內，在所有測試之俯仰率條件下，皆維持於輕度失速（light stall）狀態。相對而言，若將動態操作之最大攻角延伸至20°（即5°至20°）或23°（即5°至23°），則全機在所有俯仰率參數下，皆必然全面陷入深度失速（deep stall）。
接著，量化分析證實，動態升力增益隨俯仰率之提高呈顯著正相關。相較於靜態基準，在最大攻角20°與23°案例中，低俯仰率（PR=10°/s）之失速臨界攻角雖提前1.2°，最大升力係數仍提升約15.8%（增量0.201）；中等俯仰率（PR=15°/s）將失速攻角推遲1.84°，升力增幅達40.97%（增量0.522）。在動態遲滯效應最強之最高俯仰率（PR=20°/s）條件下，受最大攻角範圍之影響，5°至20°與5°至23°案例之失速臨界攻角分別大幅推遲了3.6°與3.96°，其動態升力則分別獲致50.79%（增量0.647）與53.05%（增量0.676）之顯著提升。此外，也探討了主翼和水平尾翼之間的尾流相互作用對 T-67 的空氣動力學影響。
最後，探討了主翼尾流與水平尾翼之交互作用，於上仰行程，主翼後緣渦流（TEV）之脫落與衝擊會誘發尾翼表面形成Λ型渦流，其隨後演化為拱狀渦流並脫離，導致全機升阻力與低頭俯仰力矩全面衰退。進入下俯行程時，主翼氣流重新附著所殘存之破碎渦流頻繁衝擊尾翼前緣，成為引發全機俯仰力矩震盪之主因。

This study investigates the dynamic stall characteristics of the Slingsby T-67 Firefly aircraft under varying pitch rates (10, 15, and 20°/s) and AOA ranges (5°–15°, 5°–20°and 5°–23°). URANS simulations employing the k-ω SST and γ-Reθ transition models accurately captured aerodynamic hysteresis, highlighting the transition model's necessity in preventing premature stall predictions. Results show that the 5°–15° range exhibits light stall, while extending the AOA to 20° or 23° triggers deep stall across all PRs. Higher PRs significantly intensify dynamic lift gains and stall delays. Compared to the static baseline, PR = 10°/s increases maximum lift by 15.8% despite a 1.2° earlier stall onset. Conversely, PR = 15°/s and 20°/s significantly delay the critical stall AOA (by 1.84° to 3.96°) and substantially enhance maximum lift (by 40.97% to 53.05%). Notably, at PR = 20°/s, severe hysteresis can truncate flow evolution if the pitch-down stroke begins before dynamic stall fully develops. Also investigates the aerodynamic effects of wake interaction between the main wing and horizontal tail.

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