透過對燃氣渦輪機轉子葉片中段區域進行冷卻，測量具有成角度斜肋之波浪通道整體端壁紐塞數與范寧摩擦係數，從而評估空氣熱性能係數之新穎複合熱傳增強方法。測試的雷諾數、旋轉數和浮力數分別在5000-15000、0-0.4、0-0.183範圍內。受肋條及波浪側壁共同作用，靜態通道的端壁平均紐塞數提高到Dittus-Boelter標準的4.77-4.90倍。沿流場方向的紐塞數與通過波浪側壁的喉部及隆起處流體的加速及減速具有高度相關。透過旋轉，在靜態通道中的高熱傳區域分別收縮與擴張於旋轉情況的穩定及不穩定壁上。最差熱傳效率是發生在旋轉數0.05時，迎風壁與背風壁發現的熱傳效率分別為靜態通道的0.77倍和0.82倍。透過將旋轉數由0增加到0.4，穩定壁上的紐塞數會先減小，後隨旋轉數增加；但范寧摩擦係數則為不斷增加。在旋轉不穩定壁上，紐塞數與摩擦係數均隨旋轉數增強而增加。當旋轉通道中浮力相對強度增強時，迎風壁與背風壁上的局部紐塞數會增加，而對其分佈趨勢影響可以忽略不計。通過增加雷諾數會使得旋轉通道熱性能係數降低並遵循紐塞數相對於旋轉數的變化趨勢。為幫助相關應用，設計兩組實驗相關公式，以評估此波浪雙通帶肋通道的區域平均紐塞數和范寧摩擦係數。

The heat transfer enhancement of the internal cooling channel in a gas turbine rotor blade plays an important role for power density and thermodynamic efficiency. The present experimental study investigates the aerothermal performance of the radially rotating two-pass wavy channel with angled ribs on the two opposite flat channel endwalls. The detailed Nusselt number (Nu) distributions on the leading (LE) and trailing (TE) rotating endwalls and the Fanning friction factor (f) at the test conditions specified by Reynolds (Re), rotation (Ro) and buoyancy (Bu) numbers in the respective ranges of 5,000-15000, 0-0.4, and 0-0.183. On each of the leading and trailing endwalls, the inlet leg (IL), turning region (TR), outlet leg (OL) and the entire endwall area (A) are specified to evaluate the regionally averaged Nusselt numbers in terms of , , , and respectively. To highlight the heat-transfer and pressure-drop augmentations, the Nusselt numbers and Fanning friction factors evaluated at the same tested Re by the Dittus-Boelter (Nu∞) and Blasius (f∞) correlations are selected as the reference to normalize Nusselt numbers and Fanning friction factors detected from the present test channel symbolized as Nu0 and f0 at the static conditions and Nu and f at the rotating conditions. The ratios of Nu/Nu0 and f/f0 hence indicate the rotating-to-static Nusselt number and Fanning friction factor ratios. The efficiency of the present enhanced test channel is indexed by the thermal performance factor (TPF) evaluated at the constant pumping power condition.
In the static channel at the Reynolds numbers of 5000-15000, the ratios of /Nu∞, /Nu∞, /Nu∞, and /Nu∞ are in the range of 4.85-4.63, 4.15-3.98, 5.34-5.23, and 4.9-4.77 respectively. The corresponding f0/f∞ ranges for LE, TE, inner sidewall, outer sidewall and for the average endwall are 35.06-38.70, 35.12-38.76, 31.59-34.64, and 32.79-34.42 respectively. The TPF values at the tested Re from 5000 to 15000 are raised to 1.53-1.45. Affecting by the Coriolis force and buoyancy force at the current tested Re, Ro and Bu, the ratios of Nu/Nu0 for the IL, TR, OL regions and over the entire endwall on the rotating LE (TE) are 0.77-1.81 (1.26-2.01), 1.06-2.06 (1.05-1.93) ), 1.06-2.13 (0.82-1.79) and 1.03-2 (1.02-1.9) respectively. The corresponding f/f0 ratios of LE, TE, inner wall, outer wall and channel endwall fall in the range of 1.1-1.66, 1.12-1.74, 1.07-1.6, 1.10-1.73 and 1.11-1.68 respectively. The TPF values at all the rotating test condition are increased to 2.39-1.48.
The worst heat transfer spots appear at the entry corners of the sharp bend on the rotating LE and TE at the rotation number of 0.05. At such worst condition on the spots with the lowest Nu, the Nu/Nu0 ratios over the rotating LE and TR are reduced to 0.51 and 0.56 respectively.
Two sets of empirical correlations are developed to determine the regionally average Nusselt number and the Fanning friction factor of present rotating channel.

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