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Onset of fluidization in vertically shaken granular material

Thorsten Poeschel·Thomas Schwager·Clara Saluena
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Abstract

When granular material is shaken vertically one observes convection, surface fluidization, spontaneous heap formation and other effects. There is a controversial discussion in literature whether there exists a threshold for the Froude number $Γ=A_0ω_0^2/g$ below which these effects cannot be observed anymore. By means of theoretical analysis and computer simulation we find that there is no such single threshold. Instead we propose a modified criterion which coincides with critical Froude number $Γ_c=1$ for small driving frequency $ω_0$.

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Thorsten Poeschel, Thomas Schwager, Clara Saluena. 1999-12-16. Onset of fluidization in vertically shaken granular material. https://doi.org/10.1103/physreve.62.1361

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