蒸發式冷卻應用於雲端機房節能之研究

Evaporative Cooling Applied to Energy Saving in Data Center

徐仁威(Jen-Wei Hsu)

指導教授 ： 劉耀先

國立交通大學/工學院/機械工程系所/碩士(2018年)

摘要

本研究探討在不同的液氣比、空氣溫度和噴霧方向，利用全域式液滴粒徑速度儀系統(Global Sizing Velocimetry, GSV)量測液滴大小，計算出蒸發式冷卻效率。實驗中使用雷諾數16000、32000、48000的氣流；液氣比範圍為4×〖10〗^(-5)、8×〖10〗^(-5)、1.2×〖10〗^(-4)；入口空氣溫度為40˚C~60˚C；而噴霧採用不同的噴灑方向，垂直於氣流和平行於氣流。結果顯示，當液氣比越高、增加空氣溫度和垂直於氣流之噴霧，蒸發冷卻效率會較其他來的好。所以當噴霧方向為垂直，液氣比為1.2×〖10〗^(-4)、入口空氣溫度為60˚C時，擁有最高的效率，相較於平行方向噴霧的效率高約3~23%。

關鍵字

蒸發式冷卻 ； 噴霧方向 ； 液氣比

並列摘要

In this study, we focus on effects of different liquid-gas ratios, air temperatures and spray directions on the evaporative cooling efficiency and the droplet size is measured by the global sizing velocimetry. In our experiment, the air Reynolds numbers are 16000, 32000, and 48000. The liquid-gas ratios are 4×〖10〗^(-5), 8×〖10〗^(-5), and 1.2×〖10〗^(-4). The inlet air temperature ranges from 40˚C to 60˚C and the directions of spray are vertical and parallel to the mainstream flow. The results show the higher liquid-gas ratio and air temperature produced much better evaporative cooling efficiency for the sprays vertical to the mainstream flow. When the spray is vertical to the air flow, the highest evaporative cooling efficiency is achieved and the efficiency is 3~23% higher than the spray direction parallel to the mainstream flow.

並列關鍵字

Evaporative cooling ； Spray direction ； Liquid to air ratio

參考文獻

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