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Shear-induced diffusion in dense granular fluids
Pierre Rognon1, Matthew Macaulay1
1Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, NSW 2006, Australia. pierre.rognon@sydney.edu.au matthew.macaulay@sydney.edu.au.
Soft Matter
|May 19, 2021
Summary
Shear deformation causes diffusion in granular materials, even without heat. This study explores shear-induced diffusion in dense flows, linking continuum laws to micro-mechanisms for better understanding of granular rheology.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Granular materials consist of solid, athermal grains.
- These grains exhibit motion and diffusion under shear deformation, despite being immune to thermal motion.
Purpose of the Study:
- Introduce and explain shear-induced diffusion in granular materials, particularly in dense flows.
- Present established scaling laws for continuum diffusivity.
- Relate continuum diffusivity to the micro-mechanisms of granular random walk.
Main Methods:
- Focus on dense granular flows.
- Analysis of established scaling laws for continuum diffusivity.
- Microscopic examination of granular random walk mechanisms.
Main Results:
- Established scaling laws for continuum diffusivity in dense granular flows.
- Connection between macroscopic diffusion and microscopic grain movement (random walk).
Conclusions:
- Understanding shear-induced diffusion is key to granular rheology.
- Insights may advance the study of diffusion in other soft materials.
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