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Updated: Jul 13, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Drift and diffusion in a periodic two-dimensional velocity field without attractors
F Müller1, L Schimansky-Geier, V S Zykov
1Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
Summary
Stochastic fluctuations enhance particle transport in periodic velocity fields, leading to enhanced fluxes. Noise allows particles to overcome fixed points, enabling oscillatory motion and improved transport compared to deterministic models.
Area of Science:
- Physics
- Statistical Mechanics
- Nonlinear Dynamics
Background:
- Deterministic transport in periodic velocity fields can be hindered by lines of fixed points.
- Additive noise is crucial for understanding particle dynamics beyond deterministic limits.
Purpose of the Study:
- To investigate the transport of overdamped particles in a 2D periodic velocity field.
- To analyze the effects of additive noise on particle motion and transport properties.
- To explore how noise intensity and modulation influence particle flux.
Main Methods:
- Analysis of particle dynamics in a 2D periodic velocity field with additive noise.
- Characterization of stochastic motion using probability distribution density and stationary mean velocity.
- Calculation of mean escape times from bounded domains.
Main Results:
- Additive noise makes fixed point lines penetrable, inducing oscillatory motion along tori.
- Intermediate noise intensities enhance particle transport compared to the deterministic case.
- Fast dichotomic modulation of asymmetry significantly boosts particle fluxes.
Conclusions:
- Stochasticity plays a key role in overcoming transport barriers in periodic systems.
- Noise-induced transport enhancement is a significant phenomenon in overdamped particle systems.
- Modulation strategies can be employed to further optimize particle flux in such systems.
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