Self-diffusion in inhomogeneous granular shearing flows
arXiv:2209.11540 · doi:10.1103/PhysRevE.106.L032901
Abstract
In this letter, we discuss how flow inhomogeneity affects the self-diffusion behavior in granular flows. Whereas self-diffusion scalings have been well characterized in the past for homogeneous shearing, the effect of shear localization and nonlocality of the flow has not been studied. We therefore present measurements of self-diffusion coefficients in discrete numerical simulations of steady, inhomogeneous, and collisional shearing flows of nearly identical, frictional, and inelastic spheres. We focus on a wide range of dense solid volume fractions, that correspond to geophysical and industrial shearing flows that are dominated by collisional interactions. We compare the measured values first, with a scaling based on shear rate and, then, on a scaling based on the granular temperature. We find that the latter does much better than the former in collapsing the data. The results lay the foundations of diffusion models for inhomogeneous shearing flows, which should be useful in treating problems of mixing and segregation.
References in corpus (10)
- Turbulent-like fluctuations in quasistatic flow of granular media
- Self-diffusion in dense granular shear flows
- A Microscopic Description of the Granular Fluidity Field in Nonlocal Flow Modeling
- Power-law scaling in granular rheology across flow geometries
- Subdiffusive axial transport of granular materials in a long drum mixer
- Average balance equations, scale dependence, and energy cascade for granular materials
- Tracer diffusion in granular shear flows
- Diffusion of a granular pulse in a rotating drum
- Self-Diffusion Scalings in Dense Granular Flows
- Self-diffusion in inhomogeneous granular shearing flows