How cohesion controls the roughness of a granular deposit
Anaïs Abramian1, Pierre-Yves Lagrée1, Lydie Staron1
1Sorbonne Université, CNRS, Institut Jean Le Rond d'Alembert, F-75005 Paris, France. anaisabramian@gmail.com.
Soft Matter
|November 17, 2021
Summary
Roughness in cohesive granular material surfaces reveals how grain clusters form. Surface roughness size correlates with inter-particle cohesion, offering insights into material flow properties.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Cohesive granular materials form clusters affecting flow.
- Cluster formation is hard to visualize and model in bulk materials.
Purpose of the Study:
- Investigate cohesive granular material cluster formation using surface roughness as a proxy.
- Characterize the relationship between surface roughness and inter-particle cohesion.
Main Methods:
- Analyzing the roughness of cohesive granular deposits.
- Quantifying surface roughness size and profile.
- Correlating roughness characteristics with inter-particle cohesion.
Main Results:
- Surface roughness size increases with inter-particle cohesion.
- The roughness profile exhibits self-affine behavior, similar to crack paths.
- A simple method to measure inter-particle cohesion from macroscopic parameters was developed.
Conclusions:
- Surface roughness is a viable proxy for understanding cluster formation in cohesive granular materials.
- The findings enhance comprehension of cluster dynamics and provide a practical method for cohesion measurement.
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