Europhys. Lett.
Volume 65, Number 2, January 2004
Page(s) 193 - 199
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 01 January 2004
Europhys. Lett., 65 (2) , pp. 193-199 (2004)
DOI: 10.1209/epl/i2003-10072-8

Oscillatory instability in a driven granular gas

E. Khain and B. Meerson

Racah Institute of Physics, Hebrew University of Jerusalem - Jerusalem 91904, Israel

(Received 25 July 2003; accepted in final form 12 November 2003)

We discovered an oscillatory instability in a system of inelastically colliding hard spheres, driven by two opposite "thermal" walls at zero gravity. The instability, predicted by a linear stability analysis of the equations of granular hydrodynamics, occurs when the inelasticity of particle collisions exceeds a critical value. Molecular-dynamics simulations support the theory and show a stripe-shaped cluster moving back and forth in the middle of the box away from the driving walls. The oscillations are irregular but have a single dominating frequency that is close to the frequency at the instability onset, predicted from hydrodynamics.

45.70.-n - Granular systems.
45.70.Qj - Pattern formation.

© EDP Sciences 2004