V型微流道壓降行為之研究

A Study on the Behavior of Pressure Drop for Liquid Flows through V-Shaped Microchannels

朱健誠(Jiann-cherng Chu)

指導教授 ： 鄧治東

中原大學/工學院/機械工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300642

摘要

本文完成單相水流體通過水力直徑為25μm 至50μm不同幾何結構之矽材V型微流道，其流力特性之研究。於本研究中，所有試片皆以純水為主要工作流體，雷諾數範圍則由0.1至35，主要量測穩態下通過微流道之流率與壓降以分析相關之流力行為。本研究主要以可控制之注射式幫浦提供穩定之流率，並以壓差計紀錄壓降之實驗值，此外，實驗中也採用顯微鏡進行微流道間流譜之觀測。
本研究將實驗結果與傳統穩流理論作比較驗證，於低雷諾數下，研究結果發現實驗數據與古典理論值間有明顯的差異，經由實驗比較結果顯示V型微流道其實驗壓降值與摩擦因子皆低於傳統穩流理論值；而依據本研究所取得之實驗數據顯示，Poiseuille number (即fRe值)也低於傳統穩流理論值之預測，本文則針對V型微流道提供一Poiseuille number修正值與實驗值做比較，結果顯示修正值與本研究所有實驗數據有較佳的吻合趨勢。

關鍵字

單相流 ； 壓降 ； V型微流道

並列摘要

Experiments were conducted to investigate the single-phase flow characteristics of water through V-shaped silicon microchannels with hydraulic diameters ranging from 25 to 50μm and a variety of geometric configurations. In the experiments, the flow rate and pressure drop across the microchannels were measured to determine the flow characteristics at steady states. All tests were performed with pure water as the working flow, where the Reynolds numbers ranging from 0.1 to 35. A controlled syringe pump was used to provide the flow while a differential transducer was used to record the pressure drop. The experimental setup used allowed the measurements of the flow patterns within the channel using microscopic observations.
The experimental results were compared with the predictions from the conventional laminar flow theory, especially for the flow with low Reynolds numbers. A significant difference between the experimental data and the theoretical predictions was found. The comparison results indicate that pressure drop and flow friction in V-shaped microchannels are smaller than those given by the conventional laminar flow theory. Based on the data obtained in this investigation, the data show that the Poiseuille number (fRe) for the V-shaped microchannels are lower than those obtained from the conventional theory. A modified Poiseuille number for the V-shaped microchannels is found to be in good agreement with all experimental data obtained from this study.

並列關鍵字

Pressure Drop ； Single-Phase flow ； V-shaped Microchannels

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