On the spectrum behavior of vibrated granular matter

TL;DR

This study investigates the vibrational dynamics of granular matter using laser-based measurements, revealing complex cooperative behaviors and introducing a fractional Langevin model to describe the dissipative particle ensemble.

Contribution

It introduces a laser measurement technique for granular dynamics and develops a fractional Langevin framework to model complex dissipative behaviors.

Findings

Power spectra reveal different cooperative dynamics.

Fractional Langevin model effectively describes dissipative particle ensemble.

Measurements include single and multiple particles in 1D and 3D systems.

Abstract

A laser facility based on a linear image sensor with a sampling period of 100microseconds allows to investigate the dissipative dynamics of a vibrated granular matter under gravity. The laser reveals the vertical movement of an individual Zirconia-Ytria stabilized 2mm ball at the surface of a weakly excited 3D granular matter bed. The stochastic realizations are measured from the top of the container. Then, power spectra measurements reveal the different cooperative dynamics of the fluidized gap. We also carried out measurements for one steel ball and many balls in 1D and 3D systems. We fit the measured different regimes with generalized Langevin pictures. We introduce a fractional temporal operator to characterize the ensemble of dissipative particles which cannot be represented by a single Langevin particle in a complex fluid.