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Tip-multi-breaking in Capillary Microfluidic Devices.

ABSTRACT: We report tip-multi-breaking (TMB) mode of droplet breakup in capillary microfluidic devices. This new mode appears in a region embraced by Cai = 0 and lg(Cai) = -8.371(Ca0)?-7.36 with Ca0 varying from 0.35 to 0.63 on the Cai -?Ca0 phase diagram, Cai and Ca0 being the capillary numbers of inner and outer fluids, respectively. The mode is featured with a periodic, constant-speed thinning of the inner liquid tip and periodic formation of a sequence of droplets. The droplet number n in a sequence is determined by and increases with outer phase capillary number, and varies from two to over ten. The distribution of both pinch-off time and size of the droplets in a sequence is a geometric progression of common ratio that depends exclusively on and increases monotonically with the droplet number from its minimum value of 0.5 at n = 2 to its maximum value of 1 as n tends to infinity. These features can help identify the unique geometric morphology of droplet clusters and make them promising candidates for encryption and anti-fake identification.

SUBMITTER: Zhu P

PROVIDER: S-EPMC4468424 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Tip-multi-breaking in Capillary Microfluidic Devices.

Zhu Pingan P Kong Tiantian T Kang Zhanxiao Z Tian Xiaowei X Wang Liqiu L

Scientific reports 20150616

We report tip-multi-breaking (TMB) mode of droplet breakup in capillary microfluidic devices. This new mode appears in a region embraced by Cai = 0 and lg(Cai) = -8.371(Ca0) -7.36 with Ca0 varying from 0.35 to 0.63 on the Cai - Ca0 phase diagram, Cai and Ca0 being the capillary numbers of inner and outer fluids, respectively. The mode is featured with a periodic, constant-speed thinning of the inner liquid tip and periodic formation of a sequence of droplets. The droplet number n in a sequence i ...[more]

PMID: 26077155

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Dataset Information

Tip-multi-breaking in Capillary Microfluidic Devices.

Publications

Tip-multi-breaking in Capillary Microfluidic Devices.

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