Jamming transitions in a schematic model of suspension rheology

Abstract

PACS. 64.70.Pf -Glass transitions. PACS. 83.60.Rs -Shear rate dependent structure (shear thinning and shear thickening).Abstract. -We study the steady-state response to applied stress in a simple scalar model of sheared colloids. Our model is based on a schematic (F2) model of the glass transition, with a memory term that depends on both stress and shear rate. For suitable parameters, we find transitions from a fluid to a nonergodic, jammed state, showing zero flow rate in an interval of applied stress. Although the jammed state is a glass, we predict that jamming transitions have an analytical structure distinct from that of the conventional mode coupling glass transition. The static jamming transition we discuss is also distinct from hydrodynamic shear thickening.c EDP Sciences

Shear Thickening of Cornstarch Suspensions as a Reentrant Jamming Transition

“…Second, at the critical stress for thickening, a discontinuous jump of the viscosity is observed. When taken together, these results strongly resemble the theoretical proposition [11] …”

“…One possible solution to this problem proposed recently [11] is that shear thickening is due to a reentrant jamming transition. It has been suggested for glassy systems that applying a shear is equivalent to increasing the effective temperature with which the system attempts to overcome energy barriers [12].…”

“…It has been suggested for glassy systems that applying a shear is equivalent to increasing the effective temperature with which the system attempts to overcome energy barriers [12]. If now a system has a reentrant ''solid'' transition as a function of temperature, the ''solid'' phase may also be induced by the shear, leading to shear thickening [11].…”

Jamming, Two-Fluid Behavior, and “Self-Filtration” in Concentrated Particulate Suspensions

“…Fundamental studies of suspension behavior in such complex flow remain rare in comparison to the wealth of studies of soft matter under simple shear [1]. Rheometrical work on concentrated suspensions has demonstrated complicated effects such as stress-induced thickening, erratic flow response, and fluctuating viscosity [2,3].In the rheology of very concentrated suspensions and other crowded soft matter systems a concept that has excited much recent speculation [4] and theoretical and experimental work [5,6,7,8,9] is that of jamming. Here we shall define jamming as the conversion of a liquid system into a solid by imposed stress.…”

Arrest and Flow of Colloidal Glasses

“…[18]) but also on the shear stress σ. It is found that a vertex which is monotonically decreasing withγ but monotonically increasing with σ can indeed result in shear thickening, and, under some conditions, in full jamming [28]. This work is preliminary, but interesting in that it suggests how new physics (beyond two-point correlations) may need to be added to MCT before the full range of observed colloidal flow behaviour is properly described.…”