Validating N-body code chrono for granular DEM simulations in reduced-gravity environments
Affiliation
Univ Arizona, Lunar & Planetary LabIssue Date
2020-08-18Keywords
methods: numericalplanets and satellites: general
planets and satellites: surfaces
software: simulations
software: development
Metadata
Show full item recordPublisher
OXFORD UNIV PRESSCitation
Sunday, C., Murdoch, N., Tardivel, S., Schwartz, S. R., & Michel, P. (2020). Validating N-body code CHRONO for granular DEM simulations in reduced-gravity environments. Monthly Notices of the Royal Astronomical Society, 498(1), 1062-1079.Rights
© 2020 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
The Discrete Element Method (DEM) is frequently used to model complex granular systems and to augment the knowledge that we obtain through theory, experimentation, and real-world observations. Numerical simulations are a particularly powerful tool for studying the regolith-covered surfaces of asteroids, comets, and small moons, where reduced-gravity environments produce ill-defined flow behaviours. In this work, we present a method for validating soft-sphere DEM codes for both terrestrial and small-body granular environments. The open-source code CHRONO is modified and evaluated first with a series of simple two-body-collision tests, and then, with a set of piling and tumbler tests. In the piling tests, we vary the coefficient of rolling friction to calibrate the simulations against experiments with 1 mm glass beads. Then, we use the friction coefficient to model the flow of 1 mm glass beads in a rotating drum, using a drum configuration from a previous experimental study. We measure the dynamic angle of repose, the flowing layer thickness, and the flowing layer velocity for tests with different particle sizes, contact force models, coefficients of rolling friction, cohesion levels, drum rotation speeds, and gravity levels. The tests show that the same flow patterns can be observed at the Earth and reduced-gravity levels if the drum rotation speed and the gravity level are set according to the dimensionless parameter known as the Froude number. CHRONO is successfully validated against known flow behaviours at different gravity and cohesion levels, and will be used to study small-body regolith dynamics in future works.ISSN
0035-8711EISSN
1365-2966Version
Final published versionSponsors
California Institute of Technologyae974a485f413a2113503eed53cd6c53
10.1093/mnras/staa2454