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Experimental observations of oscillations and segregation in a binary granular mixture
Sparisoma Viridi1, Malte Schmick, Mario Markus
1Max-Planck-Institut für molekulare Physiologie, Postfach 500247, 44202 Dortmund, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 13, 2006
Summary
We discovered a "granular clock" where vibrating granular mixtures oscillate horizontally. This phenomenon also causes complete segregation of particles by size between compartments, a novel observation in granular physics.
Area of Science:
- Physics
- Granular Mechanics
- Complex Systems
Background:
- Granular materials exhibit complex behaviors under external stimuli.
- Understanding particle segregation and collective oscillations is crucial in granular physics.
Purpose of the Study:
- To experimentally demonstrate the existence of a "granular clock" phenomenon.
- To investigate particle segregation dynamics in vibrated granular media.
- To model and understand the observed oscillations and segregation.
Main Methods:
- Utilizing a custom experimental setup with vertically vibrated bidisperse granular media.
- Employing connected compartments to observe horizontal oscillations.
- Conducting simulations with a simple phenomenological model.
Main Results:
- Experimental evidence for horizontal oscillations with periods in minutes, termed "granular clock."
- First experimental observation of complete segregation of smaller particles into one compartment.
- Simulations phenomenologically describe the observed oscillatory behavior and segregation.
Conclusions:
- Vertical vibrations can induce macroscopic oscillations and size-based segregation in granular materials.
- The "granular clock" provides a new model system for studying collective phenomena in granular media.
- The findings open avenues for controlling granular flows and segregation.
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