三列衝擊噴流對於在流道方向角為20˚的兩個旋轉流道內部之圓弧型衝擊壁面（Concave effusion wall），於有交叉橢圓型凸起（Crossed Elliptical Pedestal, CEP）與無CEP條件下，其熱傳、壓降與氣熱性能，是透過整體紐賽數（Nu）分佈、凡寧摩擦係數（f）與氣熱性能指數（API）進行評估和比較。流道的雷諾數（Rec）、旋轉數（Roc）、密度比（Δρ/ρ）與浮力數（Buc）分別位於7500-18000、0-0.75、0.44-0.58與0.0441-1.51的範圍內。科氏力效應已自浮力與慣性力效應中解耦，能在旋轉條件下使TS（Trailing surface）之旋轉對靜止Nu比（Nu/Nu0）隨Roc增加而穩定升高；但在LS（Leading surface）側則導致Nu/Nu0隨Roc從1先升高後降低。鑒於文獻中報導的旋轉面上Nu/Nu0隨Roc變化的各種形態廣泛，本研究實驗驗證Δρ/ρ與Rec為造成這些不同變化的主要參數。針對兩種旋轉流道中皆會降低效率的不利浮力效應，受耗流慣性與科氏力影響的近壁流動，造成浮力與Rec和Roc間的交互作用，使得在Rec或Roc增加時浮力對熱傳的負面效應得以削弱。CEP所帶來的冷卻效應多在旋轉測試條件之下，NuCEP普遍可使高於平滑壁面（Smooth wall, SW）流道的參考值NuSW，最高提升幅度達34%。與衝擊噴流、抽氣孔及CEP有關的基本流場機制，選柱提升氣熱性能，相較於Dittus-Boelter與Blasius的參考值，SW流道將API提升至5.81-9.9倍，CEP則提升6.65-9.93倍。於高Roc與大Δρ/ρ之操作條件下，CEP帶來的氣熱性能提升最為顯著，API可較SW流道提升達30%。

This study experimentally investigates the aerothermal performance of the rotating impingement channels equipped with crossed elliptical pedestal (CEP) for gas turbine blade leading-edge cooling. Using a curved impingement wall with three rows of jets and two rows of effusion holes at a 20° channel orientation, the effects of Reynolds number (Rec), Rotation number (Roc), and fluid density ratio (Δρ/ρ) on heat transfer and flow resistance are explored under both stationary and rotating conditions. In static conditions, CEP enhances local heat transfer by disrupting boundary layers and altering crossflow behavior. It boosts heat transfer near side jets while suppressing stagnation peaks for the central jets. Under rotation, Coriolis and buoyancy forces asymmetrically influence jet momentum—weakening it on the leading surface (LS) and strengthening it on the trailing suraface (TS)—with CEP further amplifying this effect and improving local heat transfer, especially on TS surfaces. The study finds out that increasing Rec and Roc diminishes the adverse buoyancy impact on heat transfer, leading to expanded high-heat-transfer regions. The CEP configuration consistently raises Nusselt numbers and aerothermal performance indices (API) from the smooth-walled references, with Nu and API ratios up to 1.34 and 1.3, respectively. A multivariable regression model correlate Nu/Nu0 data into the functions of Rec, Roc, and buoyancy number. Overall, the CEP design offers superior cooling performance in high rotation numbers, supporting its applicability to thermal management of an advanced gas turbine rotor blade. Recommendations for future improvement include optimizing protrusion geometry and coolant distribution by adjusting nozzle diameters for caoping with the higher thermal loads.

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