Numerical simulations of granular dam break: Comparison between discrete element, Navier-Stokes, and thin-layer
Hugo A Martin1,2, Marc Peruzzetto1,3, Sylvain Viroulet1,4
1Université Paris Cité, Institut de physique du globe de Paris, CNRS, F-75005 Paris, France.
Physical Review. E
|December 20, 2023
Summary
Comparing granular flow models reveals significant differences in dynamics, despite some agreement in surface evolution and bottom stresses. This highlights the need to assess model limitations for accurate geophysical and industrial flow simulations.
Area of Science:
- Geophysics
- Fluid Dynamics
- Computational Science
Background:
- Granular flows are prevalent in natural and industrial settings.
- Physically based models (discrete, Navier-Stokes, thin-layer) exist but their comparative coherence is understudied.
- Understanding model discrepancies is crucial for accurate granular flow simulation.
Purpose of the Study:
- To compare simulations from discrete (COCD), Navier-Stokes (Basilisk), and thin-layer (SHALTOP) models for granular dam breaks.
- To assess the mutual coherence and identify discrepancies between different modeling approaches.
- To evaluate the impact of model scale on simulating granular flow dynamics.
Main Methods:
- Simulated granular dam break scenarios on horizontal and inclined planes.
- Employed three distinct modeling approaches: Convex Optimization Contact Dynamics (COCD), Basilisk, and SHALTOP.
- Analyzed free surface evolution, flow dynamics, and bottom stresses.
Main Results:
- All models reproduced free surface evolution in the horizontal case (except SHALTOP initially).
- Significant differences in modeled flow dynamics were observed, particularly during the stopping phase.
- Bottom stress measurements showed good agreement, though COCD exhibited variations due to complex granular lattices.
Conclusions:
- Granular flow models at different scales yield significantly different dynamic results.
- Despite some agreement, model-specific behaviors and limitations must be considered.
- This comparative analysis is vital for understanding uncertainties in granular flow modeling.
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