H狀碎形式微流道中熱流行為之研究

A Study on the Thermo-Fluidic Behavior of the Flow in a H-Shaped Fractal-Like Branching

張智雄(Chih-hsiung Chang)

指導教授 ： 鄧治東

中原大學/工學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900279

摘要

本研究主要係使用商用軟體CFDRC程式，以單相流體於層流下流經碎形微流道，其模組分別分歧層之總數(M)分別為2、3、4及5，針對流道內部流場進行分析探討，並比較碎形流道與平行直管流道壓降值之差異性。其流體雷諾數於174.9至1749.1之區間，工作流體為去離子水，於溫度場方面，則是由鋁塊作為模組基底針對M＝2、3及4模組進行模擬分析。
本研究分析結果顯示出其碎形流道壓降隨階層數增高下，呈非線性增加，而平行直管流道則成線性遞減，因此碎形流道壓降高於平行直管流道，於碎形流道內流體於一定雷諾數下，有二次流行為產生，且隨者雷諾數及流道寬度改變二次流發展現象。而溫度場方面，其流體雷諾數於174.9、874.6及1749.1下，其分析模組主要分平行出口及垂直出口，其結果顯示平行出口之溫度均勻度較好於垂直出口。

關鍵字

碎形微流道 ； 壓降 ； 二次流

並列摘要

This study investigated the behavior of the flow for single-phase in laminar flowing though fractal microchannel using the analysis tool-CFDRC. The fractal microchannel is M=2, 3, 4 and 5 respectively. In order to compared the pressure drop for fractal and parallel straight microchnnel. The Reynolds number was used in this study were in the range between 174.9 and 1749.1.Deionized water was used as the working fluid. In the temperature field, this study was to analysis the M=2,3 and 4 of the fractal microchannl for the aluminum.
This result obtained the relationship of pressure drop with the fractal branch is non-linear increasing. Therefore, the pressure drop of the fractal was higher than parallel straight microchnnel. In study found the secondary flow in the fractal microchannel when the Reynolds number is high the 349.8.To follow Reynolds number and width was be change the developing of secondary flow phenomenon. In the temperature field, when the flow Reynolds number was in 174.9, 874.6, 1749.1, the module was have two ways to exit, one is the vertical the other is parallel. The result was show the uniform of the parallel was better than the vertical exit.

並列關鍵字

Fractal microchannel ； Pressure drops ； Secondary flow

參考文獻

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