通过测量流动聚焦微滴发生器中的液滴间距波动来预测液滴产生速度

Prediction of Droplet Production Speed by Measuring the Droplet Spacing Fluctuations in a Flow-Focusing Microdroplet Generator.

作者信息

Zeng Wen, Xiang Dong, Fu Hai

机构信息

Department of Fluid Control and Automation, Harbin Institute of Technology, Harbin 150001, China.

State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou 310027, China.

出版信息

Micromachines (Basel). 2019 Nov 25;10(12):812. doi: 10.3390/mi10120812.

DOI:10.3390/mi10120812

PMID:31775320

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6952780/

Abstract

In a flow-focusing microdroplet generator, by changing the flow rates of the two immiscible fluids, production speed can be increased from tens to thousands of droplets per second. However, because of the nonlinearity of the flow-focusing microdroplet generator, the production speed of droplets is difficult to quantitatively study for the typical flow-focusing geometry. In this paper, we demonstrate an efficient method that can precisely predict the droplet production speed for a wide range of fluid flow rates. While monodisperse droplets are formed in the flow-focusing microchannel, droplet spacing as a function of time was measured experimentally. We discovered that droplet spacing changes periodically with time during each process of droplet generation. By comparing the frequency of droplet spacing fluctuations with the droplet production speed, precise predictions of droplet production speed can be obtained for different flow conditions in the flow-focusing microdroplet generator.

摘要

在流动聚焦微滴发生器中，通过改变两种不混溶流体的流速，生产速度可从每秒几十滴提高到每秒数千滴。然而，由于流动聚焦微滴发生器的非线性，对于典型的流动聚焦几何结构，液滴的生产速度很难进行定量研究。在本文中，我们展示了一种有效的方法，该方法可以精确预测在很宽的流体流速范围内的液滴生产速度。当在流动聚焦微通道中形成单分散液滴时，通过实验测量了液滴间距随时间的变化。我们发现，在每次液滴生成过程中，液滴间距随时间呈周期性变化。通过将液滴间距波动的频率与液滴生产速度进行比较，可以获得流动聚焦微滴发生器中不同流动条件下液滴生产速度的精确预测结果。