We are not able to resolve this OAI Identifier to the repository landing page. If you are the repository manager for this record, please head to the Dashboard and adjust the settings.
A non-hydrostatic depth-averaged model for dry granular flows is proposed, taking into account
vertical acceleration. A variable friction coefficient based on the μ(I) rheology is considered.
The model is obtained from an asymptotic analysis in a local reference system, where the nonhydrostatic
contribution is supposed to be small compared to the hydrostatic one. The nonhydrostatic
counterpart of the pressure may be written as the sum of two terms: one corresponding
to the stress tensor and the other to the vertical acceleration. The model introduced here is weakly
non-hydrostatic, in the sense that the non-hydrostatic contribution related to the stress tensor is
not taken into account due to its complex implementation. The motivation is to propose simple
models including non-hydrostatic effects. In order to approximate the resulting model, a simple
and efficient numerical scheme is proposed. It consists of a three-step splitting procedure, and it is
based on a hydrostatic reconstruction, which allows us to obtain a well-balanced scheme. Two key
points are: (i) the friction force has to be taken into account before solving the non-hydrostatic
pressure. Otherwise, the incompressibility condition is not ensured; (ii) both the hydrostatic and
the non-hydrostatic pressure are taken into account when dealing with the friction force. The model
and numerical scheme are then validated based on several numerical tests, including laboratory
experiments of granular collapse. The influence of non-hydrostatic terms and of the choice of the
coordinate system (Cartesian or local) is analyzed. We show that non-hydrostatic models are
less sensitive to the choice of the coordinate system. In addition, the non-hydrostatic Cartesian
model produces deposits similar to the hydrostatic local model as suggested by Denlinger & Iverson
[12], the flow dynamics being however different. Moreover, the proposed model, when written in
Cartesian coordinates, can be seen as an improvement of their model, since the vertical velocity is
computed and not estimated from the boundary conditions. In general, the non-hydrostatic model
introduced here much better reproduces granular collapse experiments compared to hydrostatic
models, especially at the beginning of the flow. The error on the thickness distribution for ≤ 16◦,
at final time, is around 15% for the hydrostatic model, while it is approximately 7% for the nonhydrostatic
model. An important result is that the simulated mass profiles up to the deposit and
the front velocity are greatly improved. As expected, the influence of the non-hydrostatic pressure
is shown to be larger for small values of the slope.Ministerio de Economía y Competitividad MTM2015-70490-C2-2-RMinisterio de Ciencia, Innovación y Universidades RTI2018-096064-B-C22European Research Council (ERC) ERC-CG-2013-PE10-617472 SLIDEQUAKE
Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.