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Updated: Aug 2, 2026
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Published on: March 5, 2014
Onset of fluidization in vertically shaken granular material
1ICA 1, Universitat Stuttgart, Pfaffenwaldring 27, D-70569 Stuttgart, Germany and Institut fur Physik, Humboldt-Universitat zu Berlin, Invalidenstrasse 110, D-10115 Berlin, Germany.
Summary
Granular materials shaken vertically exhibit complex behaviors. This study finds no single Froude number threshold for these effects, proposing a modified criterion instead.
Area of Science:
- Physics of granular materials
- Nonlinear dynamics
- Fluid mechanics
Background:
- Vertical shaking of granular materials induces phenomena like convection and fluidization.
- A debated topic concerns a critical Froude number threshold for these effects.
Purpose of the Study:
- To investigate the existence of a single threshold Froude number for granular convection and related phenomena.
- To resolve the controversy regarding the critical Froude number in vertically shaken granular systems.
Main Methods:
- Theoretical analysis of granular dynamics.
- Computer simulations of vertically driven granular materials.
Main Results:
- The study demonstrates that a single, universal threshold Froude number does not govern the observed effects.
- A modified criterion is proposed, which aligns with the critical Froude number of 1 at low driving frequencies.
Conclusions:
- The observed phenomena in shaken granular materials are not determined by a single critical Froude number.
- A new criterion offers a more accurate prediction, especially for systems driven at lower frequencies.
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