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Updated: Jun 3, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Diffusion between evolving interfaces
Janne Juntunen1, Juha Merikoski
1Department of Physics, University of Jyväskylä, Jyväskylä, Finland. janne.k.juntunen@jyu.fi
Summary
Particle diffusion in dynamic environments is complex. Bubble size and interface behavior significantly influence diffusion rates, even with simple repulsion rules.
Area of Science:
- Physics
- Materials Science
- Statistical Mechanics
Background:
- Understanding particle diffusion is crucial in various scientific fields.
- Dynamic environments introduce complexities not present in static systems.
- Previous models often simplify the interaction between particles and their surroundings.
Purpose of the Study:
- To investigate diffusion dynamics in an evolving, confined environment.
- To model the behavior of continuous-time random walkers in a system with dynamic interfaces.
- To determine the factors governing diffusion in a constrained, evolving space.
Main Methods:
- Utilized continuous-time Monte Carlo simulations.
- Modeled diffusion using continuous-time random walkers on a lattice.
- Introduced dynamic bubbles between two symmetrically driven one-dimensional interfaces.
Main Results:
- In one-dimensional systems, bubble size distribution was the primary factor controlling diffusion.
- For two-dimensional random walkers, interface topography and dynamics also played a significant role.
- One-dimensional results were reproduced in the limit of strongly driven interfaces.
Conclusions:
- Diffusion in evolving environments is highly sensitive to interface properties and dynamics.
- Even simple particle-interface repulsion rules lead to complex diffusion behaviors.
- The findings provide insights into particle transport in dynamic, confined systems.
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