在本研究中探討了兩個配置蛇型肋–槽化流道蒸發器的泵驅動熱虹吸環路（PTL）的熱性能，其中一個具有內部引流，另一個則沒有。在本研究中比較了每個環路的沸騰流動結構、熱力循環、相變熱傳和熱阻，以凸顯兩組泵驅動熱虹吸環路之間熱性能指標和效率參數的差異。
有內部引流的情況下，顯著的壓力降低使得蒸發器的沸騰溫度降低，同時也使蒸發器的過冷區域縮小，進一步提升了泵驅動熱虹吸環路的性能。評估總熱阻和總泵功率的增益指數確認了蒸發器內部引流對熱性能的明顯改善。相較於無內部引流的泵驅動熱虹吸環路，總熱阻減少了3-32%，性能係數提高了14-207%。本文利用沸騰數、雷諾數和冷凝器的無因次熱阻作為控制參數，生成計算兩個PTL整體熱阻的迴歸公式。

An experimental study that explores the thermal performances of two pumped thermosyphon loops (PTL) equipped with the evaporator constructed by the serpentine multiple ribbed passages without or with bypass slots is carried out. The measurements of boiling flow structures, thermodynamic cycles, heat transfer rates with phase change activities, and overall thermal resistance form the two PTLs are compared. The various thermal performance parameters of these two TPLs are compared to enlighten the effect of internal effusion on the thermal performance indices and heat transfer efficiency for this type of TPL. The pressure-drop reduction caused by the internal effusion in the multi-pass ribbed channel considerably reduces the saturation temperature in the evaporator with the accompanying shrinkage of the sub-cooling regime for thermal performance improvement of the PTL. The performance indices accounting the reductions in overall thermal resistance and pumping power consumption of the PTL confirm the favorable contribution of the internal effusion among the multi-pass ribbed channel of the evaporator. The overall loop resistance and the coefficient of performance of the present PTL are respectively reduced by 3-32% and 14-207% from those without the effusion. A set of empirical correlations that calculates the overall thermal resistance of each PTL is devised with the boiling number, Reynolds number and dimensionless thermal resistance as the controlling variables to assist the relevant applications.

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