Length scales and self-organization in dense suspension flows

Gustavo Düring, Edan Lerner, Matthieu Wyart

    Research output: Contribution to journalArticle

    Abstract

    Dense non-Brownian suspension flows of hard particles display mystifying properties: As the jamming threshold is approached, the viscosity diverges, as well as a length scale that can be identified from velocity correlations. To unravel the microscopic mechanism governing dissipation and its connection to the observed correlation length, we develop an analogy between suspension flows and the rigidity transition occurring when floppy networks are pulled, a transition believed to be associated with the stress stiffening of certain gels. After deriving the critical properties near the rigidity transition, we show numerically that suspension flows lie close to it. We find that this proximity causes a decoupling between viscosity and the correlation length of velocities ξ, which scales as the length lc characterizing the response to a local perturbation, previously predicted to follow lc∼1/zc-z∼p0.18, where p is the dimensionless particle pressure, z is the coordination of the contact network made by the particles, and zc is twice the spatial dimension. We confirm these predictions numerically and predict the existence of a larger length scale lr∼p with mild effects on velocity correlation and of a vanishing strain scale δγ∼1/p that characterizes decorrelation in flow.

    Original languageEnglish (US)
    Article number022305
    JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
    Volume89
    Issue number2
    DOIs
    StatePublished - Feb 18 2014

      Fingerprint

    ASJC Scopus subject areas

    • Statistical and Nonlinear Physics
    • Statistics and Probability
    • Condensed Matter Physics

    Cite this