Aging to non-Newtonian hydrodynamics in a granular gasA. Astillero1 and A. Santos2
1 Departamento de Informática I, Centro Universitario de Mérida, Universidad de Extremadura - E-06800 Mérida, Spain
2 Departamento de Física, Universidad de Extremadura - E-06071 Badajoz, Spain
received 14 December 2006; accepted in final form 7 March 2007; published April 2007
published online 3 April 2007
The evolution to the steady state of a granular gas subject to simple shear flow is analyzed by means of computer simulations. It is found that, regardless of its initial preparation, the system reaches (after a transient period lasting a few collisions per particle) a non-Newtonian (unsteady) hydrodynamic regime, even at strong dissipation and for states where the time scale associated with inelastic cooling is shorter than the one associated with the irreversible fluxes. Comparison with a simplified rheological model shows a good agreement.
45.70.Mg - Granular flow: mixing, segregation and stratification.
05.20.Dd - Kinetic theory.
47.50.-d - Non-Newtonian fluid flows.
© Europhysics Letters Association 2007