Collapse of a rectangular well in a quasi-two-dimensional granular bed
Simon J de Vet1, Bereket Yohannes, K M Hill
1Department of Physics and Astronomy, University of Western Ontario, London, Ontario, Canada N6A 3K7. sdevet@dal.ca
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
Granular collapse in a rectangular well shows self-similar surface profiles, independent of initial dimensions. Particle friction is key to energy dissipation during this two-stage collapse process.
Area of Science:
- Geophysics
- Fluid Dynamics
- Materials Science
Background:
- Granular materials exhibit complex flow behaviors under gravity.
- Understanding collapse dynamics is crucial for predicting geological events and material processing.
Purpose of the Study:
- To experimentally and numerically investigate the gravity-driven collapse of a rectangular well in a granular bed.
- To analyze the influence of initial aspect ratio on collapse dynamics and final surface profiles.
- To model the collapse using continuum and discrete element methods.
Main Methods:
- Experiments using a vertical Hele-Shaw cell with high-speed video recording.
- Particle image velocimetry (PIV) to measure subsurface velocity fields.
- Depth-averaged continuum model and discrete element model (DEM) for numerical simulations.
Main Results:
- Observed two distinct collapse stages: gravity-dominated and dissipation-dominated.
- Final surface profiles were found to be self-similar, independent of the initial aspect ratio.
- Both continuum and DEM models accurately reproduced experimental results.
Conclusions:
- The aspect ratio influences collapse dynamics but not the final self-similar surface profile.
- Particle friction is identified as the primary dissipation mechanism in the discrete element model.
- The study provides validated models for granular collapse under gravity.
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