流體於歧管式微型裝置流道內流場不均勻狀況數值分析

Numerical analysis of flow mal-distribution in the multi-channel microdevices

蘇仁寶(Jen-Pao Su)

指導教授 ： 鄧治東

中原大學/工學院/機械工程學系/碩士(2007年)

https://doi.org/10.6840/cycu200700608

摘要

本研究係使用CFD-RC流力數值分析軟體，於層流條件下分別針對具Z型及U型微流道結構之幾何其長度大小、排列方式、分佈空間及出入口影響等因素探討幾何設計對於流體分佈均勻性之影響，水力直徑範圍介於65至100 μm之間，流速分佈範圍則介於0.1 m/s至1 m/s，研究結果顯示若適切改變入口速度大小、出入口方向、流道長度及分佈空間區域範圍可明顯改善流場分佈之均勻性，於同一試件，其上5流道間之相對最大速度差異介於2%~35%；此外，Z型模組與U型模組在入口流速大小對於流體均勻性的影響上為前者之流速愈大則其流體均勻性則愈差，但後者之流速愈大則其流體均勻性則愈佳，此兩模組於入口流速大小對於流體均勻性的影響上呈現相反之結果。

關鍵字

歧管 ； 微流道 ； 不均勻度

並列摘要

This study investigated the mal-distribution of flow and pressure field for single-phase low Reynolds number flow through Z-type and U-type multi-microchannel devices. In addition, comparisons were made among channel length, channel arrangement, chambers length and direction of entrances and exits. The hydraulic diameters used in this study are in the range between 65 and 100 μm; the flow rates, 0.1 to 1 ms-1.
The results obtained from simulation indicate that there is a significant improvement in the flow uniformity by modifying inlet flow rate, direction of the entrances and exits, branched channel length, and chambers length. For the test specimens under study, the highest differences among the relative velocities of the five channels on them are in the range of 2%~35%. In addition, for the Z-type multi-microchannel devices, the higher the flow velocity, the worse it becomes for the uniformity of the flow in channels; while for the U-type, the higher the flow velocity, the better it is for the uniformity. The two types of channel designs behave completely opposite to each other as far as the relationship between the flow velocity and the flow uniformity in the channels.

並列關鍵字

Microchannel ； mal-distribution ； multi-channel

參考文獻

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