本文提出一附帶螺旋翅翼之創新柱鰭陣列作為新型管道被動式傳熱增益裝置。藉由商業編譯軟體模擬通道雷諾數5500、7500、10000、15000和20000情況時紊流流場結構。基於實驗量測相同狀態下詳盡端壁紐塞數分佈與通道摩擦係數，以進行空氣傳熱特性與流場結構交互分析，探討傳熱主導機制和相關流場現象。流體穿越管道柱鰭列兩相臨柱鰭間時，受圓柱鰭上成對螺旋翅翼引導，產生各式渦旋和循環流進而強化傳熱、促進管核與管壁間流體混合。隨著雷諾數由5500增加至20000過程，端壁平均紐塞數與平滑圓管紐塞數參考值之比值由5.4下降至5.03；相對應范寧摩擦係數與平滑圓管范寧摩擦係數參考值之比值則由107.6上升至114.93。相較各式幾何形狀柱鰭陣列通道之管流，螺旋翅翼柱鰭陣列通過顯著地壓力損失實現更高傳熱性能增益。透過定泵功率以及定流量條件分析體現本柱鰭陣列傳熱效率。最終，針對通道端壁平均紐塞數與范寧摩擦係數實驗數據生成相關經驗公式，以利評估螺旋翅翼陣列通道執行與實際運用。

The current study proposes an innovative spiral-wing pin fin array as a new type of passive heat transfer enhancement (HTE) means. The aerothermal performances of the channel with the spiral-wing pin fin array are experimentally and numerically studied at the Reynolds numbers between 5500 and 20,000. The numerical simulation is carried out using the commercial software ANSYS-Fluent. The heat transfer characteristics and flow structures are interactively analyzed to determine the dominant flow physics relevant to the heat transfer performance. When the coolant flows through two adjacent pin-fins in a pin-row, it is tripped by the spiral wings attached on a cylindrical pin to generate various vortical flows to raise the endwall heat transfer rate by promoting the core-to-wall fluid mixings. When Reynolds number is increased from 5500 to 20,000, the ratio of endwall average Nusselt number to the plain tube reference is increased to 5.4-5.03. But the Fanning friction factors are raised to 107.6-114.93 times of the plain tube levels. The thermal performance factors evaluated at constant pumping powers in the range of 1.14-1.04 demonstrate the favorable aerothermal performance of the present HTE method. To assist the relevant applications, the empirical correlations evaluating the endwall average Nusselt number and Fanning friction factor of the present pin-fin channel are generated based.

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