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Updated: Jul 19, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Turbulence and coarsening in active and passive binary mixtures
S Berti1, G Boffetta, M Cencini
1Dipartimento di Fisica Generale and INFN Università di Torino, Via Pietro Giuria 1, I-10125 Torino, Italy.
Physical Review Letters
|December 31, 2005
Summary
Fluid phase separation dynamics are arrested by strong stirring, leading to a stable state with continuous domain formation and rupture. This coarsening arrest is independent of flow type.
Area of Science:
- Fluid dynamics
- Materials science
- Statistical physics
Background:
- Phase separation is a fundamental process in materials science and fluid dynamics.
- Understanding the dynamics of phase ordering is crucial for controlling material properties.
- External forces, like stirring, can significantly alter phase separation behavior.
Purpose of the Study:
- To investigate the effects of external stirring on two-dimensional fluid phase separation.
- To analyze the phase ordering process under different flow conditions.
- To determine the conditions under which coarsening arrest occurs.
Main Methods:
- Direct numerical simulations were employed.
- Coupled Navier-Stokes and Cahn-Hilliard equations were solved.
- An external stirring force was applied to the velocity field.
Main Results:
- Sufficiently strong stirring arrests the coarsening process.
- A stationary dynamical state is reached, characterized by continuous domain rupture and formation.
- Coarsening arrest was observed for both active and passive mixtures.
- The arrest phenomenon was found to be independent of whether the flow was chaotic or regular.
Conclusions:
- External stirring can effectively halt phase separation coarsening in two-dimensional fluid systems.
- A novel dynamical state of arrested coarsening exists, maintained by continuous domain dynamics.
- The mechanism of coarsening arrest is robust and not dependent on the specific nature of the applied flow.
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