複合平板迴路式熱管流量效應之研究

The Study on the Effect of Flow Rate for Hybrid Flat Plate Loop Heat Pipe

王為浩(Wei-Hao Wang)

指導教授 ： 陳瑤明

國立臺灣大學/工學院/機械工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201701308

摘要

在現今電子產業蓬勃發產下，不論是在資料中心，電腦等應用端上，各項電子元件隨著功率密度的提高，散熱的需求亦逐步上升，因此當傳統散熱方式不敷使用時，就必須開發出新的方案解決此一問題，而迴路式熱管由於具備傳輸距離長以及高功率密度散熱之特性，將非常適合應用於此散熱問題上。

此研究在傳統平板迴路式熱管中加入液體幫浦，稱為複合平板迴路式熱管，利用幫浦所提供之推力，能有效提升傳統迴路式熱管之熱傳性能，工作流體為丙酮，比較各毛細結構（銅，鎳，鐵氟龍）和無毛細結構在各流量下之性能表現，期望作為應用於電子產業如資料中心上時的一個重要參考依據。

實驗結果顯示，在複合平板迴路式熱管中，當流量超過特定範圍時，不同材質的毛細結構熱傳性能差異不大。但當流量在特定範圍內時，不同材質的毛細結構會對複合平板迴路式熱管造成較顯著之性能差異。且在特定範圍內，性能較傳統迴路式熱管提升最顯著的流量為0.3L/min，並將限制條件設為蒸發器壁面溫度100℃：對鐵氟龍而言，最大熱傳量從傳統迴路式熱管的125W提升至400W，上升約200%，熱阻也從0.209℃/W降至0.099℃/ W；對鎳而言，最大熱傳量從迴路式熱管的100W提升至400W，上升約300%，熱阻也從0.280℃/ W降至0.108℃ / W；對銅而言，最大熱傳量從傳統迴路式熱管的80W提升至400W，上升約400%，熱阻也從0.354℃/ W降至0.118℃/ W。因此鐵氟龍為較佳之毛細結構，因其熱阻及蒸發器壁面溫度都較其他兩者來的更低

綜合研究結果，不論毛細結構的材質，在泵推力的輔助之下，熱傳性能皆有顯著的提升，對於未來更高功率密度之電子產業而言，有極大的發展潛力。

關鍵字

複合平板迴路式熱管 ； 流量 ； 銅 ； 鎳 ； 鐵氟龍

並列摘要

Under the vigorous development of the electronics,whether the data centers or consumer electronic product,the demand of cooling increases with the raises of power density.The traditional cooling method wont be able to keep up with the trend,so we should come up with alternatives to solve the problem.Loop Heat Pipe(LHP) system often characterized by long transmission distance and high power density of cooling.Hence,it will be suitable for application of the demand of cooling.

This study attempts to add pump in LHP system named Hybrid Loop Heat Pipe(HLHP).The heat transfer performance improves effectively by means of the pumping force provided by pump.The working fluid is acetone.Compare the heat transfer performance with wicks made of Nickel,Copper,PTFE and without wick in evaporator at different flow rates. Expectation as an important reference when applied to electronics such as data centers.

Experimental results show that there are little differences between the heat transfer performance of different material of wick as the flow rate over a specific range.However,there are significant differences between the heat transfer performance of different material of wick as the flow rate within a specific range.Within this particular range,the heat transfer performance improves most at a rate of 0.3L/min compare to LHP.Set the temperature of evaporator limit to 100℃.As to PTFE,the maximum heat transfer from 125W up to 400W,the thermal resistance from 0.209℃/W down to 0.099℃/ W.As to Nickel,the maximum heat transfer from 100W up to 400W,the thermal resistance from 0.280℃/W down to 0.108℃/ W.As to Copper,the maximum heat transfer from 80W up to 400W,the thermal resistance from 0.354℃/W down to 0.118℃/ W.With the lowest thermal resistance and lowest evaporator temperature,PTFE is the best material in HLHP system.

In summary,no matter what the material of the wick is,heat transfer performance improve significantly by adding a pump.Hence,HLHP has extreme potential for high power density industry in the future.

並列關鍵字

Hybrid Flat Plate Loop Heat Pipe ； Flow rate ； Copper ； Nickel ； Teflon

參考文獻

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