Injected power and entropy flow in a heated granular gasP. Visco1, 2, A. Puglisi1, A. Barrat1, E. Trizac2 and F. van Wijland1, 3
1 Laboratoire de Physique Théorique (CNRS UMR8627) Bâtiment 210, Université Paris-Sud, 91405 Orsay cedex, France
2 Laboratoire de Physique Théorique et Modèles Statistiques (CNRS UMR8626) Bâtiment 100, Université Paris-Sud, 91405 Orsay cedex, France
3 Pôle Matière et Systèmes Complexes (CNRS UMR7057) - Université Denis Diderot (Paris VII) - 2 place Jussieu, 75251 Paris cedex 05, France
received 8 July 2005; accepted in final form 2 August 2005
published online 2 September 2005
Our interest goes to the power injected in a heated granular gas and to the possibility to interpret it in terms of entropy flow. We numerically determine the distribution of the injected power by means of Monte Carlo simulations. Then, we provide a kinetic-theory approach to the computation of such a distribution function. Finally, after showing why the injected power does not satisfy a fluctuation relation à la Gallavotti-Cohen, we put forward a new quantity which does fulfill such a relation, and is not only applicable in a variety of frameworks outside the granular world, but also experimentally accessible.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
05.20.Dd - Kinetic theory.
45.70.-n - Granular systems.
© EDP Sciences 2005