DENSE GRANULAR FREE-SURFACE FLOWS: COMPARISON BETWEEN μ(I)-RHEOLOGY AND DEM SIMULATION

Abstract

We have performed a systematic simulation study of dry, granular, gravity-driven, free-surface steady flow in two-dimension, investigating the rheology of cohesionless granular particles in rough inclined plane geometries by discrete element method (DEM). DEM simulation results are compared to a widely accepted μ(I)-rheology model. Microscopic parameters such as coefficient of inter-granular friction and particle size distribution are changed to investigate the influence on macroscopic behaviors like velocity field, volume fraction and effective bulk friction qualitatively. It turned out that more polydisperse system and more frictional particles leads to a low volume fraction and high effective friction. Influence of the inter-granular friction becomes stronger when it is smaller than 1 and becomes weak rapidly when it increases continuously.