Newtonian droplet generation in shear-thinning fluids in flow-focusing microchannel

被引：0

作者：

Chen Q. ^{[1
]}

Li J. ^{[1
]}

Song Y. ^{[2
]}

He Q. ^{[1
]}

Christopher D.M. ^{[2
]}

Li X. ^{[1
]}

机构：

[1] Institute of Thermal Science and Technology, Shandong University, Jinan, 250061, Shandong

[2] Department of Energy and Power Engineering, Tsinghua University, Beijing

来源：

Huagong Xuebao/CIESC Journal | 2020年 / 71卷 / 04期

关键词：

Flow-focusing microchannel; Microfluidics; Multiphase flow; Non-Newtonian fluids;

D O I：

10.11949/0438-1157.20191331

中图分类号：

学科分类号：

摘要：

The interFoam solver in the open source CFD software OpenFOAM was used to numerically simulate the formation of micro-droplets in a flow-focused microchannel. Predictions using the volume-of-fluid(VOF) model and the power-law non-Newtonian model were first validated against measurements in the literature. Then, the formation of Newtonian droplets in power-law shear-thinning fluids was modeled in three different flow regimes. The results illustrate the effects of the power-law index(n) and the consistency coefficient(K) of the power-law fluid on the droplet generation. The results show that the minimum width of the stretching thread has a power-law relationship with using the remaining time in the droplet release cycles in the squeezing and dripping regimes. The thread length increases slowly during the collapse stage and then grows rapidly during the pinch-off stage. The final droplet length decreases with increasing n or K. However, the generation frequency increases as n or K increase. The results also show that n has a greater effect than K on the droplet formation. © All Right Reserved.

引用

页码：1510 / 1519

页数：9

共 26 条

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