Physical Review Letters
We study fluctuations in the force at the boundary of a 2D granular flow. The forces are mainly impulsive at all flow rates. The probability distribution of impulses decays exponentially at large impulses, as do the forces in a static granular medium. At small impulses, the distribution evolves continuously with flow rate with no indication of the transition from collisional flow to intermittently jamming flows. However, the distribution of the time interval between collisions tends to a power law, P(τ)∼τ−3/2, showing a clear dynamical signature of the approach to jamming.
©2002 American Physical Society
Longhi, Emily; Easwar, Nalini; and Menon, Narayanan, "Large Force Fluctuations in a Flowing Granular Medium" (2002). Physics: Faculty Publications, Smith College, Northampton, MA.