本文主旨為利用數值方法探討外部對流邊界條件下圓管內相變化微粒懸浮流體之共軛熱傳現象。數值模擬所考慮的相關參數及其範圍為：相變化懸浮微粒體積濃度(0~0.2)、比爾特數 (0.1~100)、史蒂芬數 (0.01~0.2)、貝克勒數 (100~1000)、管壁面厚度比 (0~0.5)及熱傳導係數比 (0.1~10)。結果發現在考慮管壁熱傳導效應下相變化微粒濃度、史蒂芬數、比爾特數、貝克勒數與管壁熱傳導係數比之變化量均對於管內相變化微粒流體對流熱傳影響甚巨，並且在比爾特數0.1、史蒂芬數0.01、貝克勒數100 、管壁熱傳導係數比0.1 ～ 10 條件之下其流體與能量變化最為明顯。而文中也發現到於低貝克勒數、高管壁與純流體熱傳導係數比下，相變化懸浮流體熱傳效應會有明顯的往前、後延伸之現象，並且能夠幫助降低於下游出口完全絕熱段之溫度。而由文中內壁面紐賽線圖之分佈結果看來，具有較高的流體潛熱量（懸浮微粒體積濃度0.2、史蒂芬數為0.01）下，會幫助內壁面之熱傳效果提升。

　This study aims to investigate numerically the effect of conjugate heat transfer on forced convection of phase-change materials (PCM) suspensions in a circular duct with external convection boundary condition. Wall conduction as well as the axial conduction of the numerical model is taken into consideration. Numerical simulations have been undertaken for the pertinent dimensionless parameters in the ranges as follows: the volumetric concentration of the PCM particles (0~0.2), the Stefan number (0.01~0.2), the Peclet number (100~1000), the dimensionless wall thickness (0~0.5), the thermal conductivity ratio of the wall to the PCM suspending fluid (0.1~10). The result shows that the parameters of the PCM suspension fluid such like the volumetric concentration of the PCM particles, the Stefan number, the Peclet number and the thermal conductivity ratio of the wall to the PCM suspension fluid can strongly effect the convection heat transfer behaviors. At low Peclet number and high thermal conductivity ratio, it was found that significant heat conduction effect tends to extend upstream and hence the PCM particles start to freeze prior to entering the heat transfer section.

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