Inhomogeneous cooling of the rough granular gas in two dimensions
1 The Institute of Mathematical Sciences, CIT Campus - Taramani, Chennai-600113, India
2 Department of Physics, Indian Institute of Technology - Bombay, Powai, Mumbai-400076, India
Received: 10 July 2014
Accepted: 29 July 2014
We study the inhomogeneous clustered regime of a freely cooling granular gas of rough particles in two dimensions using large-scale event-driven simulations and scaling arguments. During collisions, rough particles dissipate energy in both the normal and tangential directions of collision. In the inhomogeneous regime, translational kinetic energy and the rotational energy decay with time t as power laws and . We numerically determine and , independent of the coefficients of restitution. The inhomogeneous regime of the granular gas has been argued to be describable by the ballistic aggregation problem, where particles coalesce on contact. Using scaling arguments, we predict and for ballistic aggregation, being different from that obtained for the rough granular gas. Simulations of ballistic aggregation with rotational degrees of freedom are consistent with these exponents.
PACS: 47.57.Gc – Granular flow / 47.70.Nd – Nonequilibrium gas dynamics
© EPLA, 2014