本研究提出之內設扭旋片柱鰭陣列，為新穎之被動式熱傳強化方式，可提升管流熱傳性能。本研究在雷諾數為5000、7500、10000、12500及15000的測試條件，量測扭旋片柱鰭陣列管道之紐賽數、范寧摩擦係數、熱性能係數。本研究使用ANSYS-Fluent作為模擬程式，對紊流管道內之熱性能及流場結構進行相關性分析。本論文使用一組熱傳數據及流場模擬結果，說明管道熱傳強化機制及相關的流場現象。由於扭旋片陣列所誘發的渦流強化熱傳性能，本實驗量測的管道壁面平均紐賽數與范寧摩擦係數分別為平滑管流的5.26 - 4.73及39.44 - 38.46倍，其熱性能係數於5000≤Re≤15000之範圍提升至1.55 - 1.39。與不同幾何形狀的柱鰭陣列比較，本研究所使用之扭旋片柱鰭陣列在相似的壓損條件，提高了熱傳強化性能，以及定泵功率條件下評估之熱性能係數。內設扭旋片柱鰭陣列管道之熱傳強化性能及熱性能係數之提升，確認此被動式熱傳強化裝置於工程應用之可行性。

The present study investigates the hydrothermal performance of a rectangular channel enhanced by the newly devised twisted-tape pin-fin array. The flow characteristics are studied using ANSYS-Fluent code. The simulation flow results are applied for the interpretation of the heat-transfer and pressure-drop measurements. The simulation and the experimental turbulent flow conditions are identical at Reynolds numbers of 5000, 7500, 10000, 12500 and 15000. The experimental results show that the Nusselt numbers and Fanning friction factors of the present enhanced channel are in the respective ranges of 5.26-4.73 and 39.44-38.46 times of the plain tube references, leading to the thermal performances between 1.55 and 1.39 at 5000≤Re≤15000. The thermal performance factors detected from the present test channel are raised from that with the conventional pin-fin channels. The increased heat transfer rates along with the improved thermal performance factors confirm the applicability of the twisted-tape array for heat transfer enhancements.

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