Internal energy fluctuations of a granular gas under steady uniform shear flow

TL;DR

This paper investigates the fluctuations of internal energy in a dilute granular gas under steady shear flow, comparing theoretical predictions with simulations, highlighting good agreement at low inelasticity and discrepancies at higher inelasticity.

Contribution

It extends a recent fluctuation theory from homogeneous cooling to steady shear flow in granular gases and compares predictions with molecular dynamics simulations.

Findings

Good agreement between theory and simulations at weak inelasticity

Discrepancies increase with higher inelasticity levels

Discussion on the origin of deviations at higher inelasticity

Abstract

The stochastic properties of the total internal energy of a dilute granular gas in the steady uniform shear flow state are investigated. A recent theory formulated for fluctuations about the homogeneous cooling state is extended by analogy with molecular systems. The theoretical predictions are compared with molecular dynamics simulation results. Good agreement is found in the limit of weak inelasticity, while systematic and relevant discrepancies are observed when the inelasticity increases. The origin of this behavior is discussed.