Steady Representation of the Homogeneous Cooling State of a Granular Mixture

The study of a freely evolving granular mixture using particle simulations presents the inherent limitation that, as a consequence of the inelasticity of collisions, the system is continuously cooling. Therefore, the typical particle velocities become very small rather soon, and numerical uncertainties very large. This difficulty can be solved by mapping the properties of the freely evolving granular mixture into those of a stationary state by means of a change in the time scale, similarly as it is done in one-component systems. This steady state representation will be used to study some properties of dilute granular mixtures by using the Direct Simulation Monte Carlo method. We will focus on the temperature ratio of the two components of the mixture, as well as on the fluctuations of the total energy of the mixture, as well as of each of the components.Ministerio de Economía y Competitividad del Gobierno de España FIS2011- 2446