本研究主旨在以實驗方法探討矩形微流道內部低Re條件下流場的熱傳行為。實驗利用溫度感測分子調配成溫度感測溶液與溫度感測塗料並使用傳統尺度流道的進行螢光溫度量測技術驗證，同時應用於微流體溶液中進行流體平均溫度與流道壁面溫度量測以及熱傳分析。此量測方法屬於非侵入式的光學量測方式，具有高精密度與高空間解析度等優點。由於微流道體積較小，難以架設溫度感測器，因此溫度感測分子技術適合應用在量測微流道內的溫度分佈。微流道以標準黃光製程製作出梳狀微流道母模結構，再以聚二甲基矽烷(PDMS)翻模出微流道，微流道尺寸長40 mm，寬與高分別為200 μm至900 μm以及22 μm至110 μm不等，水力直徑變化從40 μm至196 μm，深寬比維持0.1，Re範圍從15至80。
使用溫度感測分子可大幅提高空間解析度最高可達15μm/pixel , 資料點 2656個；而溫度解析度，可達0.8 ℃。溫度量測結果發現，壁面與流體溫度成長的趨勢已與巨觀尺度的線性變化不盡相同，而呈現曲線的變化。經分析後發現在微流道內，由於特徵尺度的縮小導致流場Re降低，會增加軸向熱傳的影響。當Re越低，管道中溶液溫度變化的曲率也越大；同時，因軸向熱傳的影響增強入口加熱的效應，在入口區域的溫度梯度會上升。而當水力直徑變小時，也會增加軸向熱傳的影響，也使得有相同的現象發生。在本研究中進行的實驗條件下，熱完全發展區的Nu值約為2.56，Gz-1/2約為0.48，與前人定壁溫條件下微流道熱傳分析所量測Nu值為2.24相比較高。此趨勢與傳統尺度下或微尺度下的熱傳分析一致。

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