Motion of grains in a vibrated U-tube

J. R. Darias; I. Sanchez; G. Gutierrez

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arXiv · 1001.2544

Motion of grains in a vibrated U-tube

J. R. Darias·I. Sanchez·G. Gutierrez

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Abstract

We investigate experimentally the behavior of the rate of growth of a column of grains, in a partially filled vertically shaken U-tube. For the set of frequencies used we identify three qualitatively different behaviors for the growth rate $γ$ as a function of the dimensionless acceleration $Γ$: 1) an interval of zero growth for low $Γ$ with a smooth change to nonzero growth, analogous to a continuous phase transition; 2) a sigmoidal region for $γ$ at intermediate values of the dimensionless acceleration $Γ$; and 3) an abrupt change from high values of $γ$ to zero growth at high values of $Γ$, similar to a first order phase transition. We obtain that our data is well described by a simple differential equation for the change of the growth rate with the dimensionless acceleration of the vertical vibrations.

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J. R. Darias, I. Sanchez, G. Gutierrez. 2010-01-14. Motion of grains in a vibrated U-tube. https://arxiv.org/abs/1001.2544

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