本文以實驗量測的方式，探討將水以及0.5%體積百分濃度之氧化鋁奈米流體通入毫/微米流道疊置雙層熱沉之熱傳増益與壓降。毫/微米流道疊置雙層熱沉是在一微米流道熱沉上再疊置一毫米流道熱沉所組成，毫米流道及微米流道皆以無氧銅為材料進行線切割加工而成，流道總寬度皆為16.8mm，總長度為50mm，其中毫米流道熱沉有8條長度50mm、寬度0.7mm、高度2.8mm的矩形流道，水力直徑為1.12mm，微米流道熱沉有16條長度50mm、寬度0.4mm、高度1.4mm的矩形流道，水力直徑為0.62mm。實驗以固定入口溫度40℃以及加熱面平均壁溫為實驗條件，並且在不同加熱面平均壁溫下，會有三種體積流量的工作流體通入毫/微米流道疊置雙層熱沉，在加熱面平均壁溫45℃時，體積流量分別為271.63(cm^3/min)、407.45(cm^3/min)和543.26(cm^3/min)，於加熱面平均壁溫50℃，體積流量分別為259.95(cm^3/min) 、389.93(cm^3/min) 和519.91(cm^3/min)，由實驗結果得知在高加熱面平均壁溫且高體積流量的條件下，毫/微米流道疊置雙層熱沉通入(奈米流體/純水)之有效壓降會有11%的增幅。在高加熱面平均壁溫且高流量比的條件下，毫米流道不論通入奈米流體或是純水都能夠為實驗模組提供較好的散熱幫助。

In the present study, the heat transfer effectiveness, and pressure drop of a mini-and micro-channel stacked double-layer heat sink are discussed, in which water and volumetric concentration of 0.5% alumina–water based nanofluid are coolants. The material of microchannel and minichannel heat sink is oxygen-free copper. Both channels are made by electrical discharge machining. The testing section includes minichannel heat sink which has 16 rectangular channels and a microchannel heat sink with 8 rectangular channels. The dimension of microchannel and minichannel heat sink is 50mm 0.4mm 1.4mm and 50mm 0.7mm 2.8mm, respectively. The hydraulic diameter of microchannel and minichannel is 0.62mm and 1.12mm, respectively. The experiment is under a fixed inlet temperature of 40 °C as well as two different average wall temperatures of the heating surface. Three volumetric flow rates of working fluids passing into the mini-and micro-channel stacked double-layer heat sink. The volumetric flow rate includes 271.63(cm^3/min), 407.45(cm^3/min), and 543.26(cm^3/min) under the average wall temperature of the heating surface is 45°C. When the average wall temperature of the heating surface is up to 50°C, the setting of the volumetric flow rate changes to 259.95(cm^3/min), 389.93(cm^3/min), and 519.91(cm^3/min), respectively.
The results of the experiment can be seen that when nanofluid and water are filled with minichannl and microchannel, respectively, the pressure drop increases 11% under a high average wall temperature of the heating surface. Whether the working fluid is nanofluid or water, the minichannel can provide better heat dissipation for the experimental module under a high average wall temperature of the heating surface and a high flow rate ratio.

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