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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
Hydrodynamic irreversibility in particle suspensions with nonuniform strain
Jeffrey S Guasto1, Andrew S Ross, J P Gollub
1Department of Physics, Haverford College, Haverford, Pennsylvania 19041, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
Particle suspensions exhibit a delayed transition to irreversible behavior under nonuniform shear flow. Long-range correlated particle motion, even in low-strain areas, prevents reversible states, differing from uniform shear dynamics.
Area of Science:
- Fluid dynamics
- Soft matter physics
- Rheology
Background:
- Particle suspensions can transition from reversible to irreversible behavior under oscillatory shear.
- Uniform shear flow dynamics are well-understood, but nonuniform shear presents different challenges.
Purpose of the Study:
- Investigate the dynamics of particle suspensions under nonuniform oscillatory shear (e.g., channel flow).
- Understand the onset and mechanisms of irreversibility in these systems.
Main Methods:
- Simulations or experiments involving particle suspensions in oscillatory channel flow.
- Analysis of particle motion, strain distribution, and system dynamics.
Main Results:
- Nonuniform shear delays the onset of irreversibility compared to uniform shear.
- Irreversibility onset is simultaneous across the channel.
- Long-range correlated particle motion occurs even in negligible strain regions.
- Existing models of self-organization and shear-induced migration partially explain the observed behavior.
Conclusions:
- Nonuniform shear flow significantly alters the dynamical phase transition in particle suspensions.
- Correlated particle motion plays a crucial role in preventing reversible states, even where shear is minimal.
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