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Updated: May 23, 2026
09:08
Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering
Published on: February 6, 2014
Inhomogeneous shear flows in soft jammed materials with tunable attractive forces
Pinaki Chaudhuri1, Ludovic Berthier, Lydéric Bocquet
1Laboratoire PMCN, Université Claude Bernard Lyon 1, Villeurbanne, France.
Summary
Soft jammed materials exhibit inhomogeneous shear flows at low shear rates. Attractive forces intensify these flow heterogeneities, offering new insights into shear localization mechanisms.
Area of Science:
- Soft matter physics
- Computational materials science
Background:
- Soft jammed materials display complex flow behaviors under shear.
- Understanding shear localization is crucial for predicting material failure.
Purpose of the Study:
- To investigate shear flow inhomogeneities in 2D soft jammed materials.
- To analyze the impact of attractive inter-particle forces on flow behavior.
Main Methods:
- Molecular dynamics simulations were employed.
- Simple shear flow was imposed using rough walls.
- Systems with purely repulsive and attractive interactions were studied.
Main Results:
- Pronounced flow inhomogeneities arise at low shear rates for all interaction types.
- Attractive forces increase the magnitude and lifetime of flow deviations.
- Inhomogeneities occur within a stress window defined by yield stresses.
Conclusions:
- Attractive forces enhance flow heterogeneities by accelerating stress relaxation.
- This study provides a detailed, simulation-based mechanism for adhesion's effect on shear localization.
- Findings offer a qualitative departure from prior theoretical models.
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