Gas–liquid flow stability and bubble formation in non-Newtonian fluids in microfluidic flow-focusing devices

被引：1

作者：

Taotao Fu

Youguang Ma

Denis Funfschilling

Huai Z. Li

机构：

[1] Tianjin University,State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology

[2] Nancy-Université,Laboratory of Reactions and Process Engineering

[3] CNRS,undefined

来源：

Microfluidics and Nanofluidics | 2011年 / 10卷

关键词：

Microfluidics; Gas–liquid flow; Bubble; Flow-focusing device; Micro-PIV;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

This communication describes the gas–liquid two-phase flow patterns and the formation of bubbles in non-Newtonian fluids in microfluidic flow-focusing devices. Experiments were conducted in two different polymethyl methacrylate (PMMA) square microchannels of, respectively, 600 × 600 and 400 × 400 μm. N2 bubbles were generated in non-Newtonian polyacrylamide (PAAm) solutions of different concentrations. Slug bubble, missile bubble, annular and intermittent flow patterns were observed at the cross-junction by varying gas and liquid flow rates. Gas and liquid flow rates, concentration of PAAm solutions, and channel size were varied to investigate their effect on the mechanism of bubble formation. The bubble size was proportional to the ratio of gas/liquid flow rate for slug bubbles and could be scaled with the ratio of gas/liquid flow rate as a power–law relationship for missile bubbles under wide experimental conditions.

引用

页码：1135 / 1140

页数：5

共 72 条

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