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Scaling behavior of coarsening Faraday heaps
Henk Jan van Gerner1,2, Ko van der Weele3, Devaraj van der Meer1
1Faculty of Science and Technology, University of Twente, NL-7500 AE Enschede, The Netherlands.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 14, 2015
Summary
Shaking sand creates conical Faraday heaps that merge over time. Their coarsening dynamics depend on sand availability, with heap size growing as t(1/2) or t(1/3).
Area of Science:
- Physics
- Complex Systems
- Granular Dynamics
Background:
- Vertically shaken granular layers form complex patterns.
- Faraday heaps are conical structures observed in granular experiments.
- The dynamics of these heaps involve merging and coarsening over time.
Purpose of the Study:
- To model the dynamics of Faraday heap formation and merging.
- To analytically determine the scaling laws for heap lifetime and diameter growth.
- To compare theoretical predictions with experimental observations.
Main Methods:
- Development of a theoretical model for heap dynamics.
- Analytical derivation of scaling relationships for heap lifetime.
- Analysis of heap diameter growth under different sand availability conditions.
Main Results:
- The mean lifetime of the transient state with N heaps scales as N(-2).
- In abundant sand conditions, average heap diameter grows as t(1/2).
- In limited sand conditions, average heap diameter grows as t(1/3).
Conclusions:
- The proposed model accurately describes Faraday heap coarsening.
- Sand availability is a critical factor influencing heap growth rates.
- Theoretical predictions align well with experimental findings in granular physics.
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