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Asymmetric velocity correlations in shearing media
1Department of Physics, Umeå University, 901 87 Umeå, Sweden.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
This study simulates frictionless disks to understand sheared systems. Velocity correlations reveal identical diagonal behaviors and link rotational fields to plastic events.
Area of Science:
- Soft Matter Physics
- Computational Physics
- Statistical Mechanics
Background:
- Sheared systems exhibit complex behaviors.
- Understanding particle dynamics in these systems is crucial.
- Asymmetries can significantly alter system properties.
Purpose of the Study:
- To investigate asymmetries in two-dimensional sheared systems of soft frictionless disks.
- To analyze single particle properties and spatial velocity correlations.
- To develop and utilize a correlation function for separating rotational fields.
Main Methods:
- Simulated a model of soft frictionless disks in 2D.
- Employed shearing dynamics for system manipulation.
- Analyzed single particle properties, spatial velocity correlation functions, and rotational field correlation functions.
Main Results:
- Observed that velocity correlations along compression and dilation diagonals are nearly identical.
- Identified a direct relationship between a feature in correlation functions and irreversible plastic events.
- Characterized distinct clockwise and counterclockwise rotational fields.
Conclusions:
- The study reveals fundamental insights into the behavior of sheared soft matter.
- Identical diagonal velocity correlations suggest underlying symmetries despite applied shear.
- Plastic events in these systems are intrinsically linked to rotational dynamics.
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