本研究將一組不同攻角之結構物放入截面寬高500 m×100 m之PDMS矩形微流道，並以液態金屬作為加熱器置於流道側壁面，在側壁加熱的條件下，探討結構物對流場及溫度場的影響。實驗之雷諾數為10、20、30及40，在量測溫度場上使用之實驗技術為溫度螢光感測塗料(Temperature Sensitive Paint, TSP)，而速度場則使用微粒子影像測速法(Micro-Particle Image velocity, micro-PIV)進行量測，最後加入壓力量測評估整體熱傳效益，以無因次熱傳性能參數η作為判斷整體效益的基準，找出最合適之攻角設計。
本研究使用直管道以及10°、20°及30°攻角之結構物流道，以TSP實驗取得液體溫度後並討論使用高階多項式擬合以及近壁面資料一階線性方式進行擬合估算壁面溫度與熱通量，研究結果顯示近壁面之溫度分布近似於斜直線，使用一階線性擬合有較好的準確性。接著討論在不同角度及雷諾數下，溫度場及速度場皆受到一定程度的影響，在相同攻角下，雷諾數的增加將使平均紐賽數提升，其原因為拍攝位置仍處於熱發展中階段，紐賽數較大；在相同雷諾數下，結構物攻角愈大，造成之局部紐賽數提升峰值愈大，在30°時的峰值可達到直管道的兩倍以上。對30°結構物攻角雷諾數40局部紐賽數的影響範圍，以結構物起點開始，影響範圍包括往上游約0.5個結構物單位長度(x/pitch)，往下游最遠不超過3 x/pitch；而對速度場的影響範圍往上游最遠可超過3 x/pitch，往下游最遠可超過4 x/pitch，上下游的速度影響範圍皆達到拍攝視野邊界。
最後以η進行整體之熱傳綜合效益，雖然攻角愈大能產生更大的平均紐賽數，但伴隨的壓損也會上升，若將壓損考慮進綜合效益η值，20°的結構物在所有雷諾數下皆擁有較大的η值，且在雷諾數20時η=1.177為本研究表現最佳之參數，而全部參數下之η值皆大於1，因此在此三種攻角下之熱傳綜合效益皆為正面影響。

This study aims to investigate the heat transfer enhancement of the rectangular PDMS microchannels with inclined flat plates at different attack angles. The channel was 500 m wide and 100 m deep respectively. Liquid metal was chosen as the heater and was placed at the parallel channel aside of the main channel. The Reynolds number in current experiment was varied from 10 to 40. Temperature and velocity fields were obtained by Temperature sensitive paint (TSP) and micro-particle image velocity (micro-PIV) techniques. In addition, pressure measurement between channel inlet and outlet was conducted to evaluate the hydraulic performance by using the dimensionless thermal performance factor η, and the performance of microchannels with inclined flat plats compared with straight channel was discussed.
In TSP measurement, two analysis methods using high order polynomial curve fitting and linear curve fitting for fluid temperature profiles were proposed for extracting the information of wall temperature and heat flux. The linear curve fitting showed better accuracy in the experimental results. Under the condition of the same AOA (angle of attack) for inclined flat plate, higher Reynolds number would lead to higher averaged Nusselt number. This is due to the selected region of interest in the measurement which is still within the thermal developing region. On the other hand, when the Reynolds number was fixed as a constant, inclined flat plate with higher AOA would introduce higher increment of the local Nusselt number. For 30°AOA, the peak value of Nusselt number could be as much as two times more than that in the straight channel. It has been observed that the range of the improved local Nusselt number covered upstream and downstream of the object with 0.5 x/pitch (units length of the flat plate) and 3 x/pitch, respectively, at Reynolds number of 40 and 30°AOA flap plate. It has been also noted that the influence of velocity field extended 3 x/pitch upstream and 4 x/pitch downstream of the object, which has reached the margin of view of interest in the experimental arrangement.
Finally, dimensionless quantity η was calculated to evaluate the hydraulic performance compared with straight microchannel. Although the higher attack angle could bring out larger averaged Nusselt number, it would be accompanied with the higher pressure loss. The experimental results showed that all cases with inclined flat plates had η value greater than 1, which means that the hydraulic performance were all improved in these three conditions. Among them, the inclined flat plate with 20°AOA showed the best η values in the Reynolds number from 10 to 40.

摘要 I
Abstract III
誌謝 V
目錄 VI
圖目錄 VIII
表目錄 XIII
符號說明 XIV
第1章、 緒論 1
1.1 研究動機 1
1.2 文獻回顧 3
1.2.1 微尺度熱傳分析 3
1.2.2 溫度螢光感測塗料(TSP) 10
1.2.3 微粒子影像測速法(μ-PIV) 16
1.2.4 結構物干擾流場之研究 20
1.3 研究目的 26
第2章、 實驗原理 27
2.1 溫度螢光感測塗料(TSP) 27
2.2 微粒子影像測速法(μ-PIV) 29
2.3 熱傳分析 31
第3章、 實驗方法 33
3.1 微流道製作 33
3.2 溫度量測系統 37
3.2.1 實驗架設 37
3.2.2 校正曲線 40
3.2.3 TSP分析方式 41
3.3 速度量測系統 46
3.3.1 μ-PIV實驗架設 46
3.3.2 訊號產生器之時序設定 47
3.3.3 螢光粒子的選用 49
3.4 壓力量測實驗架設 51
第4章、 直管道驗證 52
4.1 溫度場驗證 52
4.2 速度場驗證 60
4.3 實驗不確定性分析 62
4.3.1 溫度場量測不確定性分析 62
4.3.2 速度場量測不確定性分析 63
第5章、 結構物流道與直管道實驗結果分析 64
5.1 結構物設計 64
5.2 溫度場量測 66
5.3 速度場量測 80
5.4 壓差量測及整體熱傳效益討論 91
第6章、 結論與未來建議工作 95
6.1 結論 95
6.2 未來工作與建議 97
參考文獻 98
附錄 102

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