1,3,- 1Université Paris Cité, Institut de Physique du Globe de Paris, Sismology, Paris, France (anne.mangeney@gmail.com)
- 2Laboratoire d’Analyse et de Mathématiques Appliquées, Université Gustave Eiffel, CNRS-UMR 8050, F-77454, Marne-la-Vallée, France.
- 3Departamento Matemática Aplicada I, Universidad de Sevilla. E.T.S. Arquitectura. Avda, Reina Mercedes, s/n. 41012 Sevilla, Spain.
To effectively assess the growing hazard related to debris flows, it is crucial to simulate these natural
grain-fluid flows at a reasonable computational cost. To complement existing depth-averaged grain-fluid flow
models with an upper-fluid layer, we propose here a model with an upper-solid layer, as a first step towards the
development of unified models describing all possible configurations. This model accounts for granular mass
dilatancy and pore fluid pressure feedback and solves for solid and fluid velocity in the mixture and for the
upper-solid velocity. Simulation in uniform configurations reveals the rich behaviour of the flow and shows that
the upper-solid and upper-fluid models may predict very different behaviour. Our work highlights the need of
developing two-layer models accounting for dilatancy and unifying upper-solid and upper-fluid configurations
in the same framework.
How to cite: Mangeney, A., Bouchut, F., Fernandez-Nieto, E., and Narbona-Reina, G.: A depth-averaged grain-fluid model with dilatancy and an upper-solid layer, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5017, https://doi.org/10.5194/egusphere-egu26-5017, 2026.
