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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Rheology of dense granular mixtures: boundary pressures
1Saint Anthony Falls Laboratory, Department of Civil Engineering, University of Minnesota, Minneapolis, Minnesota 55414, USA.
Physical Review Letters
|March 17, 2011
Summary
Granular material pressure depends on more than just average particle size. Effective free volume per particle is key for understanding sheared granular mixtures and their complex rheology.
Area of Science:
- Granular physics
- Rheology
- Computational mechanics
Background:
- Rheological properties of dense sheared granular materials are known to depend on particle size.
- The representative particle size for granular mixtures remains unclear.
- Understanding granular material behavior is crucial in various industrial applications.
Purpose of the Study:
- To computationally investigate the pressure exerted by sheared granular mixtures on a boundary.
- To determine how this pressure depends on the particle size distribution.
- To identify key parameters governing the rheological properties of granular mixtures.
Main Methods:
- Computational modeling of dense sheared granular materials.
- Analysis of boundary pressure in response to varying particle size distributions.
- Adaptation of packing expressions to quantify effective free volume per particle.
Main Results:
- Boundary pressure in sheared granular mixtures does not exhibit a monotonic dependence on average particle size.
- Pressure is influenced by a measure of effective free volume per particle.
- The findings challenge simple models based solely on average particle size.
Conclusions:
- Effective free volume is a critical factor in the rheology of sheared granular mixtures.
- Particle size distribution, not just average size, governs granular material pressure.
- This study provides a more nuanced understanding of granular material behavior under shear.
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