Elastic energy, fluctuations and temperature for granular materialsL. Kondic1 and R. P. Behringer2
1 Department of Mathematical Sciences & Center for Applied Mathematics & Statistics New Jersey Institute of Technology, Newark, NJ 07102, USA
2 Department of Physics and Center for Nonlinear and Complex Systems Duke University, Durham, NC 27708-0305, USA
(Received 11 February 2004; accepted in final form 7 May 2004)
We probe, using a model system, elastic and kinetic energies for sheared granular materials. For large enough P/Ey (pressure/Young's modulus) and ( P/kinetic energy density) elastic dominates kinetic energy, and energy fluctuations become primarily elastic in nature. This regime has likely been reached in recent experiments. We consider a generalization of the granular temperature, , with both kinetic and elastic terms and that changes smoothly from one regime to the other. This is roughly consistent with a temperature adapted from equilibrium statistical mechanics.
45.70.-n - Granular systems.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
64.70.Pf - Glass transitions.
© EDP Sciences 2004