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Updated: Aug 28, 2025
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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Anomalous diffusion and transport by a reciprocal convective flow.
Yuki Koyano1, Hiroyuki Kitahata2
1Department of Human Environmental Science, Graduate School of Human Development and Environment, Kobe University, Kobe 657-0011, Japan.
Physical Review. E
|September 16, 2022
Summary
Cooperative effects of convection and diffusion can enhance diffusion, leading to anomalous transport. This study investigates these phenomena under reciprocal flow using numerical simulations and Langevin dynamics.
Area of Science:
- Fluid dynamics
- Statistical physics
Background:
- Convection and diffusion are typically studied separately due to differing scales.
- Cooperative effects can lead to diffusion enhancement, a phenomenon not fully understood.
Purpose of the Study:
- Investigate cooperative effects of convection and diffusion.
- Analyze anomalous diffusion and transport under reciprocal flow.
Main Methods:
- Numerical simulations of the convection-diffusion equation.
- Theoretical analysis using Langevin dynamics.
Main Results:
- Anisotropic diffusion and net shift observed.
- Diffusion enhancement confirmed under reciprocal flow.
- Anomalous diffusion and transport theoretically derived.
Conclusions:
- Cooperative effects significantly alter transport phenomena.
- Reciprocal flow induces anisotropic diffusion and enhanced diffusion.
- Langevin dynamics provide a theoretical framework for these anomalous behaviors.
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