本實驗研究探討具潛熱冷卻頂板毫米流道熱沉內氧化鋁-水奈米流體於穩態/突然脈衝熱載下散熱性能之實驗研究。毫米流道熱沉為無氧銅材料，流道總長為50mm、流道總寬為25.1mm，而單一流道截面積尺寸為寬1mm、高3mm。本實驗研究相關參數範圍：純水與重量百分濃度分別為2%、5%、8%氧化鋁-水奈米流體，粒徑約集中在100nm。
由本穩態實驗結果顯示，添加奈米顆粒確實有降低壁溫的效果，且其壓降增加並不劇烈，其平均熱傳增益皆能提升，最大增益可達41%，但具潛熱冷卻頂板加熱功率設定，並沒有發揮到效果。在突然脈衝熱載暫態結果顯示，二十二烷微膠囊層有發揮其潛熱吸收的效果，在壁溫皆能有效下降，而熱阻降幅也皆在0以上。

The present study aims to investigate an experimental study concerning forced convective heat dissipation characteristics of Al2O3-water nanofluid flow in a mini-channel heat sink under steady/sudden-pulsed power load. Two multi-channel heat sinks featuring a length of 50 mm and a width of 25.1 mm were fabricated of oxygen-free copper with eight parallel mini-channels, each with an inlet cross-section of 1 mm in width and 3 mm in height with their ceiling embedded with or without a layer of a microencapsulated phase change material (MEPCM).
The steady state experimental results obtained reveal that using the Al2O3-water nanofluid to replace the pure water as the coolant through the mini-channel heat sink can give rise to an enhancement of 41%, in the average heat transfer coefficient over that of using the pure water. In the aspect of incorporating the heat sink with its ceiling embedded MEPCM layer and hence the potential latent heat absorption effect, the steady state forced convection results reveal somewhat insignificant effects on cooling performance of Al2O3-water nanofluid. On the other hand, under the sudden-pulsed heat loads, the cooing effectiveness of using the Al2O3-water nanofluid in the heat sink with ceiling embedded MEPCM layer appears further uplifted in comparison with that without embedded MEPCM layer.

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