Kinetic theory of driven granular fluids

TL;DR

This paper investigates the transport properties of driven granular fluids modeled as inelastic hard spheres, using both analytical methods and Monte Carlo simulations to understand the effects of external driving forces.

Contribution

It provides a comprehensive analysis of driven granular gases by combining analytical approaches with computational simulations, clarifying the influence of external thermostats.

Findings

Transport coefficients determined for driven granular systems

Comparison between analytical and simulation results

Insights into the influence of external driving forces

Abstract

Granular matter under rapid flow conditions can be modeled as a granular gas, namely, a gas of hard spheres dissipating part of their kinetic energy during binary collisions (inelastic hard spheres, IHS). On the other hand, given that collisions are inelastic one has to inject energy into the system to compensate for the inelastic cooling and maintain it in rapid conditions. Although in real experiments the external energy is supplied to the system by the boundaries, it is quite usual in computer simulations to heat the system by the action of an external driving force or thermostat. Despite thermostats have been widely employed in the past, their influence on the dynamic properties of the system (for elastic and granular fluids) is not yet completely understood. In this work, we determine the transport properties of driven granular systems by using two independent and complementary routes, one of them being analytic (Chapman-Enskog method, BGK solution and Grad's moments method) and the other one being computational (Monte Carlo simulations).