1999/11/14 by Nikolai V. Brilliantov, Thorsten Poeschel, Thorsten Pöschel · 101 citations
Engineering · Environmental Science · Mathematics · Physics and Astronomy · #Classical mechanics #Coefficient of restitution #Constant (computer programming) #Dissipation #Distribution (mathematics) #Distribution function #Flow velocity #Geometry #Granular flow and fluidized beds #Landslides and related hazards #Mathematical analysis #Mathematics #Mechanics #Particle Dynamics in Fluid Flows #Physics #Relaxation (psychology) #Scaling #Thermal velocity #Thermodynamics #Viscoelasticity #cond-mat.stat-mech
paper · pdf · doi:10.1103/physreve.61.5573
published in Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics 61(5), 5573-5587 (American Physical Society) · 15 pages, 4 figures
arxiv created 1999/11/14 · openalex publication_date 2000/05/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The velocity distribution in a homogeneously cooling granular gas has been studied in the viscoelastic regime, when the restitution coefficient of colliding particles depends on the impact velocity. We show that for viscoelastic particles a simple scaling hypothesis is violated, i.e., that the time dependence of the velocity distribution does not scale with the mean square velocity as in the case of particles interacting via a constant restitution coefficient. The deviation from the Maxwellian distribution does not depend on time monotonically. For the case of small dissipation we detected two regimes of evolution of the velocity distribution function: Starting from the initial Maxwellian distribution, the deviation first increases with time on a collision time scale saturating at some maximal value; then it decays to zero on a much larger time scale which corresponds to the temperature relaxation. For larger values of the dissipation parameter there appears an additional intermediate relaxation regime. Analytical calculations for small dissipation agree well with the results of a numerical analysis.