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Updated: Mar 24, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
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Stochastic dynamics of particles trapped in turbulent flows
N Machicoane1, M López-Caballero2, L Fiabane1,3
1Laboratoire de Physique, ENS de Lyon, UMR CNRS 5672, Université de Lyon, France.
Physical Review. E
|March 18, 2016
Summary
Large particles in turbulent shear flows exhibit slow back-and-forth motion between attractors. This dynamics, influenced by particle size and flow reversals, is modeled using stochastic and extended approaches.
Area of Science:
- Fluid Dynamics
- Particle Dynamics
- Turbulence
Background:
- Studying particle dynamics in turbulent shear flows is crucial for understanding complex fluid systems.
- Large particles exhibit reduced sensitivity to flow fluctuations compared to smaller ones.
Purpose of the Study:
- Investigate the long-time dynamics of large particles in two distinct nonhomogeneous turbulent shear flows.
- Characterize particle motion, including slow dynamics and synchronization with flow reversals.
Main Methods:
- Experimental observation of large particles in turbulent shear flows.
- Development and application of a one-dimensional stochastic model with a two-well potential and colored noise.
- Extension of the model to include spatially nonhomogeneous fluctuations and confinement strength.
Main Results:
- Observed emergence of slow, back-and-forth dynamics between two attractors for large particles.
- Identified a super-slow regime synchronized with flow reversals.
- Stochastic and extended models substantially reproduced the experimental dynamics.
Conclusions:
- Particle size significantly influences dynamics in turbulent shear flows.
- The ratio of noise correlation to particle dynamics time scales is key for modeling trapping without a potential barrier.
- Spatially nonhomogeneous fluctuations and appropriate confinement are necessary for complete agreement with experimental results.
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