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Updated: Jun 29, 2026
10:32
Image-based Lagrangian Particle Tracking in Bed-load Experiments
Published on: July 20, 2017
Convection in vibrated annular granular beds.
R D Wildman1, T W Martin, P E Krouskop
1School of Mechanical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, United Kingdom.
Summary
Researchers studied granular bed vibration response using experiments and simulations. They found that controlling wall dissipation can direct convection rolls and form double rolls.
Area of Science:
- Physics
- Granular Mechanics
- Fluid Dynamics
Background:
- Granular materials exhibit complex behaviors under external stimuli.
- Understanding vibration response is crucial for industrial applications.
Purpose of the Study:
- Investigate the vibration response of a granular bed with a dissipative inner wall.
- Determine packing fraction and granular temperature distributions.
- Explore control of convection rolls using wall dissipation.
Main Methods:
- Positron Emission Particle Tracking (PEPT) for experimental analysis.
- Hard Sphere Molecular Dynamics (HSMD) simulations for numerical investigation.
- Analysis of packing fraction and granular temperature profiles.
Main Results:
- Experimental and numerical results showed good agreement.
- Toroidal convection roll direction was controllable by manipulating inner and outer wall dissipation (coefficients of restitution).
- Formation of double convection rolls was observed and experimentally confirmed.
Conclusions:
- Wall dissipation is a key parameter for controlling granular flow patterns.
- The study demonstrates a method for directing and forming complex convection rolls in vibrated granular beds.
- Findings have implications for granular material handling and process design.
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