Yang He, Knowles Tuomas P J
School of Mechanical Engineering, Hangzhou Dianzi University, No. 2 Street, Qiantang District, Hangzhou 310018, China.
Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
Micromachines (Basel). 2022 Sep 29;13(10):1640. doi: 10.3390/mi13101640.
Droplet sorting is one of the fundamental manipulations of droplet-based microfluidics. Although many sorting methods have already been proposed, there is still a demand to develop new sorting methods for various applications of droplet-based microfluidics. This work presents numerical investigations on droplet sorting with asymmetric acute junctions. It is found that the asymmetric acute junctions could achieve volume-based sorting and velocity-based sorting. The pressure distributions in the asymmetric junctions are discussed to reveal the physical mechanism behind the droplet sorting. The dependence of the droplet sorting on the droplet volume, velocity, and junction angle is explored. The possibility of the employment of the proposed sorting method in most real experiments is also discussed. This work provides a new, simple, and cost-effective passive strategy to separate droplets in microfluidic channels. Moreover, the proposed acute junctions could be used in combination with other sorting methods, which may boost more opportunities to sort droplets.
液滴分选是基于液滴的微流控技术的基本操作之一。尽管已经提出了许多分选方法，但对于基于液滴的微流控技术的各种应用，仍有开发新分选方法的需求。这项工作对具有不对称锐角结的液滴分选进行了数值研究。发现不对称锐角结可以实现基于体积的分选和基于速度的分选。讨论了不对称结中的压力分布，以揭示液滴分选背后的物理机制。探索了液滴分选对液滴体积、速度和结角的依赖性。还讨论了在大多数实际实验中采用所提出的分选方法的可能性。这项工作提供了一种新的、简单且经济高效的被动策略，用于在微流控通道中分离液滴。此外，所提出的锐角结可以与其他分选方法结合使用，这可能会增加更多分选液滴的机会。
