Partially fluidized shear granular flows : continuum theory and MD simulations.

Journal Article · Fri Aug 01 04:00:00 EDT 2003 · Phys. Rev. E

DOI:https://doi.org/10.1103/PhysRevE.68.021301· OSTI ID:961248

Volfson, D; Tsimring, L S; Aranson, I S

The continuum theory of partially fluidized shear granular flows is tested and calibrated using two-dimensional soft particle molecular dynamics simulations. The theory is based on the relaxational dynamics of the order parameter that describes the transition between static and flowing regimes of granular material. We define the order parameter as a fraction of static contacts among all contacts between particles. We also propose and verify by direct simulations the constitutive relation based on the splitting of the shear stress tensor into a 'fluid part' proportional to the strain rate tensor, and a remaining 'solid part.' The ratio of these two parts is a function of the order parameter. The rheology of the fluid component agrees well with the kinetic theory of granular fluids even in the dense regime. Based on the hysteretic bifurcation diagram for a thin shear granular layer obtained in simulations, we construct the 'free energy' for the order parameter. The theory calibrated using numerical experiments with the thin granular layer is applied to the surface-driven stationary two-dimensional granular flows in a thick granular layer under gravity.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 961248
• Report Number(s): ANL/MSD/JA-45766
• Journal Information: Phys. Rev. E, Journal Name: Phys. Rev. E Journal Issue: 2 Pt. 1 ; Aug. 2003 Vol. 68; ISSN PLEEE8; ISSN 1063-651X
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BIFURCATION
DIAGRAMS
DYNAMICS
ENERGY
FLUIDS
FUNCTIONS
GRANULAR MATERIALS
KINETICS
LAYERS
MOLECULAR DYNAMICS METHOD
ORDER PARAMETERS
PARTICLES
RHEOLOGY
SHEAR
STRAIN RATE
TENSORS