本實驗比較三組內部抽氣與無內部抽氣之肋化漸縮-漸擴急彎雙流道詳細紐賽數分佈、凡寧摩擦係數及空氣熱傳性能係數，探討內部抽氣對其熱傳強化性能產生之影響。研究重點比較分析內部抽氣角度為 0°或+22.5° 時，受抽氣角度變化影響所產生之流場結構改變，造成其紐賽數分佈自無內部抽氣熱傳、壓損特徵所產生之差異性變化。於測試雷諾數介於5000 至 15,000之範圍，抽氣管道之管壁面積平均紐賽數（凡寧摩擦係數）於0°、+22.5° 和 - 22.5°抽氣角度時，分別介於 91.39–187.68 (0.21–0.22) 、100.43–196.08 (0.17–0.19) 和 90.67–143.01 (0.22–0.22)之範圍，其對應之空氣熱傳性能係數分別為 1.74–1.33、2.07–1.47、和 1.71–1.01。應用本研究產生之實驗數據庫，回歸出計算各抽氣條件管道區域平均紐賽數和凡寧摩擦係數之實驗公式，提供相關產業與研究應用。

The present experimental study compares the detailed Nusselt number distributions, the Fanning friction factors, and the aerothermal performance indices measured from the convergent-divergent wavy two-pass ribbed channels without effusion and with the internal effusion at three angles. The effect of internal effusion on the performances of heat transfer enhancement are examined. The present research focuses on the heat-transfer and pressure-drop variations from those without effusion at the effusion angles of 0° or +22.5° owing to the attendant flow modifications. With inlet Reynolds numbers between 5,000 and 15,000 at the effusion angles of 0°, 22.5°, and - 22.5°, the area-averaged endwall Nusselt numbers (Fanning friction factors) are in the respective ranges of 91.39-187.68 (0.21-0.22), 100.43-196.08 (0.17-0.19), and 90.67-143.01 (0.22-0.22). The corresponding ranges of aerothermal performance indices are 1.74-1.33, 2.07-1.47, and 1.71-1.01, respectively. Based on the present data bank, the empirical correlations that evaluate the area-averaged endwall Nusselt numbers and Fanning friction factors without effusion and with the internal effusion at three different angles are generated to assist the relevant applications.

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