Pressure-dependent threshold in a granular flow: Numerical modeling and experimental validation

Numerical simulations, performed with a new two-phase bi-projection scheme, of the collapse columns glass beads aspect ratios equal to 0.7 and 2 over horizontal plane are reported comparison experiments presented. A level-set formulation for Navier–Stokes equations is used, so that interface between granular material ambient air tracked. The flow modeled viscoplastic rheology, derived from μ ( I ) –rheology, resulting in Drucker–Prager plasticity criterion combined spatio-temporal variable viscosity depending on pressure shear rate. computational effort reduced by using instead constant viscosity. dependence results upon value viscosity, which has been two orders magnitude, very weak suggesting these flows mainly governed criterion. rheology formulated as projection, allowing an efficient computation plastic part stress tensor. Coulomb friction conditions applied walls. dynamics morphology final deposit accurately reproduced. Sensitivity results, respect resolution basal coefficient, also studied. During collapse, consists overlain flowing layer, separated migrates upwards until layer consumed. time evolution this static-mobile quantified good agreement found experiments. To best our knowledge first simulation internal validated We report obtained model where dynamic yield replaced hydrostatic pressure, height. This produces non-physically relevant solutions. Nevertheless, numerical point view, it provides interesting challenging test cases two-phases simulations rolls up before head mass falls bottom wall. • scheme used simulate dambreak flows. Results compared experimental data beads. used. recovered. separates into layer.