許多研究顯示，平板上的薄膜冷卻流與主流的交互作用下，在冷卻孔附近會形成非對稱雙渦流(腎渦流)，以及腎渦流對薄膜冷卻效果的影響。許多薄膜冷卻流的數值研究侷限在簡單的幾何模型，例如平板，或是不可壓縮流。因此，本研究使用了CD-adapco所開發的數值分析軟體STAR-CCM+來模擬分析含薄膜冷卻的1988 C3X葉片之熱傳和空氣動力，並探討薄膜冷卻流中是否存在腎渦流的現象和薄膜冷卻流對葉片的熱傳影響。紊流模型選擇了學術界和業界常使用的紊流模型(k-ω SST和v2-f)，並從這兩種紊流模型中比較出較適合模擬渦輪葉片冷卻流的紊流模型。在進行1988 C3X葉片冷卻的模擬分析之前，本研究會先進行M6(ONERA M6)機翼的流場之模擬分析和驗證，藉由後掠翼表面的壓力係數和震波的高準確預測來增加使用CFD軟體的可信度。
模擬結果顯示，兩個紊流模型在無薄膜冷卻流的案例中，結果是相似的，然而綜合了數值計算時間、數值收斂性和數值預測準度，k-ω SST紊流模型的表現是較好的。因此，在含薄膜冷卻流的案例中，只使用了k-ω SST紊流模型來計算。k-ω SST紊流模型在含薄膜冷卻流的案例中的數值結果也相當吻合實驗結果，但對流熱傳係數的預測準度仍有待加強；模擬結果發現了腎渦流(kidney vortex)的現象，而腎渦流的抬升效應會將周圍的熱氣導引至薄膜冷卻流底下，使得薄膜冷卻效果下降，但若腎渦流受到了上游反渦流的影響，即可抑制腎渦流的抬升效應；模擬結果也發現，在葉片前緣的端牆附近產生了馬蹄渦流(horseshoe vortex)，馬蹄渦流導致了薄膜冷卻流在葉片的前緣、壓力面和吸力面的端牆附近之薄膜冷卻效果下降。本研究也探討了薄膜冷卻流對葉片的熱傳影響，結果顯示了薄膜冷卻流在葉片降溫上有顯著的幫助。後掠翼的結果顯示，兩個紊流模型的預測結果都非常的好，結果也相當一致，若綜合了數值計算時間、數值收斂性和數值預測準度，k-ω SST紊流模型的表現仍然是比較好的。

It is well known that in turbine film cooling problems, kidney vortices cause interaction between main-stream flow and coolant. These vortices cause coolant to lift-off and flow away from the wall, thus reducing film-cooling effectiveness. Most of the previous numerical studies of film cooling were limited to simple geometries such as flat plates. There have been very few numerical studies of film cooling on turbine vanes. Therefore, this study analyzes kidney vortices in turbine vanes and tries to find suitable turbulence model for the turbine cooling problems. Two turbulence models (k-ω SST and v2-f) have been used for performance comparison. Both turbulence models were first validated on a swept wing in order to validate their accuracy, and both models returned very accurate results compared with experimental data. The results show that the performance of k-ω SST model is better than v2-f in the non-film cooling cases. In the case of film cooling, it is found that kidney vortices pose vital effects on the effectiveness of film cooling. Horseshoe vortices also play an important role to reduce the film effectiveness near the end walls of the vane. The results confirm that the film cooling is very effective to cool turbine vane.

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