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Particle Dynamics at the Onset of the Granular Gas-Liquid Transition
M Noirhomme1, A Cazaubiel2, E Falcon2
1GRASP, CESAM Research Unit, Institut de Physique B5a, Sart Tilman, University of Liège, B-4000 Liège, Belgium.
Physical Review Letters
|April 9, 2021
Summary
Large tracer particles in a granular gas reveal a phase transition. Their energy equipartition signals the onset of clustering, offering a simple method to detect this granular gas-liquid shift.
Area of Science:
- Granular physics
- Complex systems
- Statistical mechanics
Background:
- Granular materials behave uniquely due to inelastic collisions and lack of dissipation.
- Understanding phase transitions in granular systems is crucial for various applications.
Purpose of the Study:
- To experimentally investigate the dynamical behavior of large tracer particles in a granular gas.
- To identify a simple and accurate method for detecting the granular gas-liquid transition.
Main Methods:
- Utilizing a quasi-2D granular gas in a low-gravity environment.
- Employing particle tracking to analyze tracer particle velocity distributions.
- Systematically increasing the density of the granular system.
Main Results:
- Tracer particle velocity distributions were analyzed as system density increased.
- Translational energy equipartition was observed at the gas-liquid transition onset.
- The emergence of local clusters coincided with this transition.
Conclusions:
- The dynamics of tracer particles serve as a sensitive indicator of the granular gas-liquid transition.
- This approach provides a simple and accurate method for detecting phase transitions in granular media.
- A model was developed to accurately describe the formation of local heterogeneities during this transition.
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