空氣微噴流散熱模組之研究

Abstract

本研究欲解決伺服器散熱問題，針對1U伺服器之有限空間放入設計流道進行衝擊冷卻。本研究包含模擬與實驗兩部分，研究參數有雷諾數(2131-5979)和三種出風口方向。 初步模擬結果中，原始流道會造成流量分佈不均，影響熱傳效能，為改善原始流道性能，本研究提出另外三種設計流道，藉由不同的流道幾何設計，改變流道內部壓力分佈進而影響流量，除了解決流量分佈不均的問題也改變熱傳分佈，甚至提升平均熱傳效能。 透過模擬定性後，本研究進一步由實驗驗證各流道造成的不同熱傳效能，實驗結果顯示，斜面式流道在高雷諾數雙向出口時，能提升原流道熱傳性能13%左右；而在相同泵功率下，階梯式流道平均熱阻能低於原流道，為本研究最佳設計。

The objective of this study is to provide an effective heat dissipation method via air-cooling applicable for 1U server. The design examines the impingement designs to tackle the high flux dissipation. The designs can be implemented in the confined space of a typical 1U server. Both numerical and experimental studies are made available in this thesis. The simulation and experiments are conducted with the Reynolds number ranging from 2131 to 5979 subject to three exit flow arrangements. In the first part of simulation, the airflow distribution of the original impingement channel is extremely non-uniform and impairs the heat transfer accordingly. To improve the heat transfer capability of the original impingement channel, this present study examines three designs to change the pressure distribution in the channels. Furthermore, influence of the flowrate distribution imposes significant influences on the local heat transfer distribution, and can be used to promote the average heat transfer performance. The following up experimental study had confirmed the heat transfer performance of the four different channels. The experiment results show that when the outflow is flowing in both directions, the slide type impingement channel could enhance about 13% heat transfer performance compared to the original impingement channel at high Reynolds number. However, the step type impingement channel has the lowest thermal resistance at the same pumping power in this study.