Build up of yield stress fluids via chaotic emulsification

• Published in: arXiv.org
• Main Authors: Girotto, Ivan, Benzi, Roberto, Gianluca Di Staso, Scagliarini, Andrea, Schifano, Sebastiano Fabio, Toschi, Federico
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 24.11.2021
• Subjects: Droplets; Elastic properties; Emulsions; Fluid flow; Phenomenology; Physics - Fluid Dynamics; Physics - Soft Condensed Matter; Polydispersity; Rheological properties; Rheology; Size distribution; Stirring; Yield strength; Yield stress
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2111.12453

Stabilized dense emulsions display a rich phenomenology connecting microstructure and rheology. In this work we study how an emulsion with a finite yield stress can be built via large-scale stirring. By gradually increasing the volume fraction of the dispersed minority phase, under the constant action of a stirring force, we are able to achieve volume fractions close to \(80\%\). Despite the fact that our system is highly concentrated and not yet turbulent we observe a droplet size distribution consistent with the \(-10/3\) scaling, often associated to inertial range droplets breakup. We report that the polydispersity of droplet sizes correlates with the dynamics of the emulsion formation process. Additionally we quantify the visco-elastic properties of the dense emulsion finally obtained and we demonstrate the presence of a finite yield stress. The approach reported can pave the way to a quantitative understanding of the complex interplay between the dynamics of mesoscale constituents and the large scale flow properties yield-stress fluids.