Transient deformation of a droplet near a microfluidic constriction: A quantitative analysis

Corentin Tregouët (1, 2) , Thomas Salez (3, 4) , Cécile Monteux (1, 4) , Mathilde Reyssat (2)

1 SIMM - Sciences et Ingénierie de la Matière Molle
2 Gulliver (UMR 7083)
3 LOMA - Laboratoire Ondes et Matière d'Aquitaine
4 Hokkaido University [Sapporo, Japan]

We report on experiments that consist of deforming a collection of monodisperse droplets produced by a microfluidic chip through a flow-focusing device. We show that a proper numerical modeling of the flow is necessary to access the stress applied by the latter on the droplet along its trajectory through the chip. This crucial step enables the full integration of the differential equation governing the dynamical deformation, and consequently the robust measurement of the interfacial tension by fitting the experiments with the calculated deformation. Our study thus demonstrates the feasibility of quantitative in situ rheology in microfluidic flows involving, e.g., droplets, capsules, or cells.

Domaines: Matière Molle [cond-mat.soft]; Mécanique des fluides [physics.class-ph]

Corentin Tregouët, Thomas Salez, Cécile Monteux, Mathilde Reyssat. Transient deformation of a droplet near a microfluidic constriction: A quantitative analysis. Physical Review Fluids, 2018, 3 (5), pp.053603. ⟨10.1103/PhysRevFluids.3.053603⟩. ⟨hal-01848466⟩