Experimental study of work exchange with a granular gas: the viewpoint of the Fluctuation Theorem

TL;DR

This paper experimentally investigates energy flux fluctuations between a granular gas and a driven oscillator, analyzing the data through the Fluctuation Theorem to identify a characteristic energy scale of the granular system.

Contribution

It provides the first experimental application of the Fluctuation Theorem to granular gases, revealing a characteristic energy scale from work fluctuation statistics.

Findings

Identified a characteristic energy $E_c$ of the granular gas.

Validated the Fluctuation Theorem in a granular system context.

Demonstrated the use of a DC motor as both actuator and probe.

Abstract

This article reports on an experimental study of the fluctuations of energy flux between a granular gas and a small driven harmonic oscillator. The DC-motor driving this system is used simultaneously as actuator and probe. The statistics of work fluctuations at controlled forcing, between the motor and the gas are examined from the viewpoint of the Fluctuation Theorem. A characteristic energy $E_c$ of the granular gas, is obtained from this relation between the probabilities of an event and its reversal.