Discontinuous shear thickening in Brownian suspensions
Takeshi Kawasaki1, Ludovic Berthier2
1Department of Physics, Nagoya University, Nagoya 464-8602, Japan.
Physical Review. E
|August 17, 2018
Summary
Discontinuous shear thickening in dense suspensions is explained by a minimal model. Thermal motion and particle softness control the crossover between frictionless and frictional jamming regimes.
Area of Science:
- Soft matter physics
- Colloidal science
- Rheology
Background:
- Discontinuous shear thickening (DST) is observed in dense suspensions.
- Existing models often neglect thermal fluctuations and particle softness.
- A complete understanding requires considering multiple competing forces.
Purpose of the Study:
- To characterize DST in colloidal suspensions using computer simulations.
- To provide a comprehensive description of DST by modeling key physical interactions.
- To establish a minimal model for quantitative interpretation of experimental DST data.
Main Methods:
- Utilizing computer simulations to model dense colloidal suspensions.
- Focusing on the interplay of athermal jamming, friction, thermal motion, particle softness, and shear flow.
- Intentionally omitting hydrodynamics, electrostatics, lubrication, and inertia.
Main Results:
- Achieving quantitative agreement with experimental findings.
- Identifying DST as a crossover between frictionless and frictional jamming.
- Demonstrating that thermal fluctuations and particle softness control this crossover.
- Showing the crossover is dependent on a softness-dependent Péclet number.
Conclusions:
- The developed minimal model captures essential physics of DST.
- Findings provide a framework for interpreting experimental DST data.
- The study clarifies the role of thermal effects and particle deformability in DST.
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