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Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Phase separation in a chaotic flow
L Berthier1, J L Barrat, J Kurchan
1Département de Physique des Matériaux, Université C. Bernard and CNRS, Villeurbanne, France.
Physical Review Letters
|April 6, 2001
Summary
Lagrangian chaos in fluid dynamics limits domain growth during liquid phase separation. Unequal liquid volumes result in an exponential droplet size distribution due to chaotic mixing.
Area of Science:
- Fluid dynamics
- Complex systems
- Statistical mechanics
Background:
- Phase separation is a fundamental process in materials science and fluid dynamics.
- Spinodal decomposition describes the early stage of phase separation.
- Lagrangian chaos describes chaotic particle trajectories in fluid flow.
Purpose of the Study:
- To investigate the effect of Lagrangian chaos on the phase separation of immiscible liquids.
- To analyze how chaotic advection influences spinodal decomposition.
- To determine the relationship between chaotic mixing and domain growth.
Main Methods:
- Numerical simulation of the Cahn-Hilliard equation for phase separation.
- Analysis of bidimensional velocity fields with varying degrees of Lagrangian chaos.
- Quantification of domain size distribution and growth rates.
Main Results:
- Fully chaotic flow significantly limits the growth of separated liquid domains.
- An exponential distribution of droplet sizes is observed for unequal liquid volume fractions in chaotic flows.
- A balance between chaotic mixing (Lyapunov exponent) and spinodal decomposition (diffusivity) determines the limiting domain size.
Conclusions:
- Lagrangian chaos plays a crucial role in controlling phase separation dynamics.
- Chaotic advection can lead to unique droplet size distributions.
- The interplay between mixing and decomposition governs the final morphology of separated phases.
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