本文主要是針對狹長紊流噴流衝擊至等熱通量加熱半圓凹面的流場與熱傳特性進行數值研究。紊流統御方程式是以控制體積法為基礎，配合冪次法則有限差分法與著名的k-epson紊流模式及其相關之牆函數來求解與描述紊流結構。此外，本文採用實體吻合曲線座標系統將物理空間轉換至計算空間。
數值計算採用以下參數，噴嘴出口雷諾數、無因次噴嘴到衝擊凹面距離H/B、無因次噴嘴寬度B/D以及熱通量。本文中所採用的理論模式經與文獻中已發表的實驗數據作數值預測值的確認。在此研究範圍中，除了無因次噴嘴到衝擊凹面距離H/B=0.5，其局部紐塞數 最大值出現偏移在S/B=1.5處，其餘H/B=4~12之局部紐塞數最大值均產生在停滯點，並沿半圓凹壁面逐漸減小。局部紐塞數之數值結果顯示合理的預測，最大誤差在15%內。當雷諾數固定時，除了低衝擊距離H/B=0.5外，衝擊距離H/B對於平均紐塞數來說的影響並不明顯。本研究對於狹長紊流噴流衝擊冷卻半圓凹面提供了基礎瞭解。

The investigation of the flow field and heat transfer characteristics of a slot turbulent jet impinging on a semi-circular concave surface with uniform heat flux has been carried out numerically in this study. The turbulent governing equations are solved by a control-volume-based finite-difference method with power-law scheme and the well-know k-epson turbulence model and its associate wall function to describe the turbulent structure. In addition, body-fitted curvilinear coordinate system is employed to transform the physical domain into a computational domain.
Numerical computations have been conducted with variations of jet exit Reynolds number, dimensionless jet-to-surface distance H/B, dimensionless jet width B/D and the heat flux. The theoretical model developed is validated by comparing the numerical predictions with available experimental data in the literature. In these studied ranges, the variations of local Nusselt numbers along the semi-circular concave surface decrease monotonically from its maximum value at the stagnation point except that at low H/B=0.5, the maximum Nu shift to S/B=1.5. The numerical results show that the local Nusselt numbers are reasonably predicted with a maximum discrepancy within 15%. As the Reynolds number fixes, the effect of the impingement distance (H/B) on the average Nusselt is not significant except at low H/B=0.5. This study provides fundamental insight into turbulent slot jet impingement cooling on the semi-circular concave surface.

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