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Anomalous velocity distributions in active Brownian suspensions
Andrea Fiege1, Benjamin Vollmayr-Lee, Annette Zippelius
1Georg-August-Universität Göttingen, Institut für Theoretische Physik, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 17, 2013
Summary
Researchers studied randomly accelerated particles using simulations and theory. They found universal, anomalous velocity distributions, suggesting a simplified one-particle model accurately describes particle behavior in suspension.
Area of Science:
- Physics
- Statistical Mechanics
- Nonlinear Dynamics
Background:
- Understanding particle dynamics in suspension is crucial for various fields.
- Previous models often oversimplified the complex interactions and accelerations involved.
Purpose of the Study:
- To determine the nonequilibrium velocity distribution of randomly accelerated particles.
- To develop and validate a theoretical model capturing particle behavior in suspension.
Main Methods:
- Combined large-scale simulations using an event-driven algorithm with friction.
- Developed and analytically solved a one-particle model in the strong damping limit.
Main Results:
- Observed anomalous, universal velocity distributions, independent of particle density and collisions.
- The one-particle model analytically predicted a 1/v decay for velocity distribution, transitioning to Gaussian at high velocities.
Conclusions:
- A simplified one-particle model effectively captures the essential features of particle acceleration in suspension.
- Simulation and analytical results show strong agreement across various damping conditions.
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