English

Breaking one into three: surface-tension-driven droplet breakup in T-junctions

Fluid Dynamics 2025-11-17 v1

Abstract

Droplet breakup is an important phenomenon in the field of microfluidics to generate daughter droplets. In this work, a novel breakup regime in the widely studied T-junction geometry is reported, where the pinch-off occurs laterally in the two outlet channels, leading to the formation of three daughter droplets, rather than at the center of the junction for conventional T-junctions which leads to two daughter droplets. It is demonstrated that this new mechanism is driven by surface tension, and a design rule for the T-junction geometry is proposed. A model for low values of the capillary number CaCa is developed to predict the formation and growth of an underlying carrier fluid pocket that accounts for this lateral breakup mechanism. At higher values of CaCa, the conventional regime of central breakup becomes dominant again. The competition between the new and the conventional regime is explored. Altogether, this novel droplet formation method at T-junction provides the functionality of alternating droplet size and composition, which can be important for the design of new microfluidic tools.

Keywords

Cite

@article{arxiv.2207.00077,
  title  = {Breaking one into three: surface-tension-driven droplet breakup in T-junctions},
  author = {Jiande Zhou and Yves-Marie Ducimetière and Daniel Migliozzi and Ludovic Keiser and Arnaud Bertsch and François Gallaire and Philippe Renaud},
  journal= {arXiv preprint arXiv:2207.00077},
  year   = {2025}
}
R2 v1 2026-06-24T12:10:24.678Z