Thermal fluctuations of granular gas driven by Gaussian thermostat based on two-point kinetic theory

TL;DR

This paper studies thermal fluctuations in a driven granular gas using two-point kinetic theory, comparing theoretical predictions with numerical simulations to understand fluctuation behavior and transport coefficients.

Contribution

It applies two-point kinetic theory to analyze thermal fluctuations in a Gaussian thermostatted granular gas, providing comparisons with DSMC simulations.

Findings

Time correlations of pressure deviator fluctuations match theoretical predictions.

Heat flux fluctuation correlations are validated against numerical results.

Transport coefficients from kinetic theory agree with DSMC calculations.

Abstract

In this paper, we investigate thermal fluctuations of the granular gas, which is driven by Gaussian thermostat, on the basis of two-point kinetic theory. In particular, we consider thermal fluctuations of the inelastic variable sphere, which was proposed by Yano [J. Phys. A, 46 (37), 375502 (2013)]. Time correlations of thermal fluctuations of the pressure deviator and two times of the heat flux are calculated on the basis of the two-point kinetic theory and compared with their numerical results, which are calculated using the direct simulation Monte Carlo (DSMC) method. Finally, we compare transport coefficients, which are calculated on the basis of the kinetic theory, with those calculated using the DSMC method.