Aravena A., Chupin L., Dubois T., Roche Olivier. (2022). Fluidisation by pore pressure of dense granular flows : numerical simulations versus experiments.
Oslo : [s.n.], 12 p. multigr. ECCOMAS : European Congress on Computational Methods in Applied Sciences and Engineering, 8., Oslo (NOR), 2022/06/05-09.
Titre du document
Fluidisation by pore pressure of dense granular flows : numerical simulations versus experiments
Année de publication
2022
Type de document
Colloque
Auteurs
Aravena A., Chupin L., Dubois T., Roche Olivier
Source
Oslo : [s.n.], 2022,
12 p. multigr.
Colloque
ECCOMAS : European Congress on Computational Methods in Applied Sciences and Engineering, 8., Oslo (NOR), 2022/06/05-09
A model accounting for fluidisation by pore gas pressure in dense granular flows is presented. A viscoplastic rheology, based on the Drucker-Prager criterium, is used to describe the granular medium which is a mixture of air and glass beads. The pore gas pressure, which satisfies an advection-diffusion equation, reduces the friction between the particles and thus the value of the apparent viscosity. As a consequence, dense fluidised granular flows can travel longer distances. In laboratory experiments, the run-out distance reached by dense granular columns when collapsing is almost doubled when fluidisation is applied. This fundamental result, in the context of pyroclastic density currents, is reproduced by numerical simulations performed with the fluidised model.
