Convection, heaping, and cracking in vertically vibrated granular slurries
J M Schleier-Smith1, H A Stone
1Division of Engineering & Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|April 6, 2001
Summary
Vibrating wet granular layers creates heap-shaped structures. Increased vibration leads to cracks, revealing a phase diagram governed by fluid dynamics and Rayleigh-Taylor instability.
Area of Science:
- Physics
- Fluid Dynamics
- Material Science
Background:
- Granular materials with pore fluid are common in nature and industry.
- Understanding their response to external forces is crucial for various applications.
Purpose of the Study:
- To investigate the behavior of thin granular layers saturated with water under vibration.
- To characterize the formation of convecting structures and their subsequent evolution.
Main Methods:
- Applying controlled vibration to saturated granular layers.
- Observing and analyzing the resulting structures using visual methods.
- Mapping the observed phenomena in a phase diagram.
Main Results:
- Heap-shaped convecting domains with nontrivial topology emerge beyond a critical vibration parameter.
- Cracks appear in these structures at higher forcing amplitudes.
- The onset of convection is linked to the Rayleigh-Taylor instability.
Conclusions:
- Vibration can induce complex self-organization in saturated granular materials.
- The Rayleigh-Taylor instability plays a key role in the formation of convecting structures.
- A phase diagram effectively summarizes the observed behaviors.
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