Dynamic compaction of cohesive granular materials: scaling behavior and bonding structures.
Max Sonzogni1,2, Jean-Mathieu Vanson1, Katerina Ioannidou2
1CEA, DES, IRESNE, DEC, Cadarache, F-13108 Saint-Paul-lez-Durance, France.
Soft Matter
|April 11, 2024
Summary
Particle-scale parameters like bond strength significantly influence cohesive granular material compaction. Simulations reveal relative porosity depends on a modified cohesion number and contact stiffness, crucial for understanding powder manufacturing.
Area of Science:
- Powder Technology
- Materials Science
- Computational Physics
Background:
- Compaction of cohesive granular materials is vital in powder-based manufacturing.
- Particle-scale parameters, including bond strength, poorly understood regarding their influence on packing structure and compaction scaling.
Purpose of the Study:
- Analyze jammed configurations from dynamic compaction of sticky particles.
- Investigate the influence of particle-scale parameters on compaction behavior.
- Understand the scaling of the compaction process.
Main Methods:
- Utilized particle dynamics simulations.
- Simulated dynamic compaction of sticky particles under fixed compressive pressure.
- Analyzed a broad range of system parameter values.
Main Results:
- Relative porosity is a unique function of a modified cohesion number (adhesion, pressure, size) and contact stiffness.
- An asymmetric sigmoidal function fits the observed data.
- Bond network properties show self-balanced forces and exponential force distribution decay.
- Bond network characteristics depend on cohesion number, not modified cohesion number, due to contact stiffness effects.
Conclusions:
- Contact stiffness plays an essential role in cohesive granular material compaction.
- The findings provide a framework for understanding and optimizing powder compaction processes.
- Deviations from general scaling are attributed to finite system size or rigid walls.
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