Gravity Governs Shear Localization in Confined Dense Granular Flows
M Reza Shaebani1, János Török2, Maniya Maleki3
1Department of Theoretical Physics and Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany.
Physical Review Letters
|January 21, 2022
Summary
Understanding granular material flow under varying gravity is key for planetary exploration. This study reveals universal scaling laws for predicting granular flow, independent of gravity for free surfaces but influenced by it under pressure.
Area of Science:
- Geophysics
- Materials Science
- Planetary Science
Background:
- Predicting granular material flow is crucial for geophysical and industrial applications.
- Understanding gravity's influence is vital for planetary exploration in diverse gravitational fields.
Purpose of the Study:
- To disentangle the effects of gravitational acceleration, confining pressure, and layer thickness on shear strain localization in granular materials.
- To develop universal scaling laws for predicting granular flow profiles.
Main Methods:
- Experimental analysis
- Variational analysis
- Principle of minimization of energy dissipation
Main Results:
- Flow profile is independent of gravity for free-surface granular layers.
- Increasing gravity promotes transition from closed to open shear zones under confinement.
- Universal scaling laws were identified for shear zone properties and surface velocity.
Conclusions:
- Granular flow profiles follow a universal master curve, enabling predictions in varying gravitational environments.
- Findings are applicable to planetary exploration and industrial granular material handling.
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