The statistics of particle velocities in dense granular flows

Abstract

We present measurements of the particle velocity distribution in the flow of granular material through vertical channels. Our study is confined to dense, slow flows where the material shears like a fluid only in thin layers adjacent to the walls, while a large core moves without continuous deformation, like a solid. We find the velocity distribution to be non-Gaussian, anisotropic, and to follow a power law at large velocities. Remarkably, the distribution is identical in the fluid-like and solid-like regions. The velocity variance is maximum at the core, defying predictions of hydrodynamic theories. We show evidence of spatially correlated motion, and propose a mechanism for the generation of fluctuational motion in the absence of shear.

arXiv commentSubmitted to Phys. Rev. Lett

References in corpus (5)

• Signatures of granular microstructure in dense shear flows
• Particle dynamics in sheared granular matter
• Time-Resolved Studies of Stick-Slip Friction in Sheared Granular Layers
• NMR Experiments on a Three-Dimensional Vibrofluidized Granular Medium
• Diffusion and mixing in gravity-driven dense granular flows

Cited by in corpus (16)

• Orientation, Flow, and Clogging in a Two-Dimensional Hopper: Ellipses vs. Disks
• Velocity correlations in dense granular flows observed with internal imaging
• Obstacle-shape effect in a two-dimensional granular silo flow field
• Anomalous diffusion in silo drainage
• Fluctuations of grains inside a discharging two-dimensional silo
• Velocity Distribution and the Effect of Wall Roughness in Granular Poiseuille Flow
• Anomalous Diffusion in a Bench-Scale Pulsed Fluidized Bed
• Growing length scale in gravity-driven dense granular flow
• Boltzmann equation for dissipative gases in homogeneous states with nonlinear friction
• Collisional regime during the discharge of a 2D silo
• Response to perturbations for granular flow in a hopper
• Dissipation and velocity distribution at the shear-driven jamming transition
• Statistical properties of gravity-driven granular discharge flow under the influence of an obstacle
• Simulations of collision times in gravity driven granular flow
• Poiseuille flow of soft polycrystals in 2D rough channels
• Skewed superstatistical distributions from a Langevin and Fokker-Planck approach