Shear-thickening and entropy-driven reentrance

TL;DR

This paper introduces a generic entropy-driven mechanism for shear-thickening, modeled through mean-field glassy systems, revealing complex phase transitions and providing a theoretical framework for shear-thickening phenomena.

Contribution

It presents a simple microscopic model that captures shear-thickening and reentrant phase behavior, deriving a Mode-Coupling theory for this phenomenon.

Findings

Identification of second and first order jamming transitions

Observation of intermittency and metastability in the phase diagram

Fragility of jammed states with respect to stirring direction

Abstract

We discuss a generic mechanism for shear-thickening analogous to entropy-driven phase reentrance. We implement it in the context of non-relaxational mean-field glassy systems: although very simple, the microscopic models we study present a dynamical phase diagram with second and first order stirring-induced jamming transitions leading to intermittency, metastability and phase coexistence as seen in some experiments. The jammed state is fragile with respect to change in the stirring direction. Our approach provides a direct derivation of a Mode-Coupling theory of shear-thickening.