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This content will become publicly available on May 1, 2026

Title: Improved velocity-Verlet algorithm for the discrete element method
The Discrete Element Method is widely employed for simulating granular flows, but conventional integration techniques may produce unphysical results for simulations with static friction when particle size ratios exceed R ≈ 3. These inaccuracies arise under certain circumstances because some variables in the velocity-Verlet algorithm are calculated at the half-timestep, while others are computed at the full timestep. To correct this, we develop an improved velocity-Verlet integration algorithm to ensure physically accurate outcomes up to the largest size ratios examined (R = 100). The implementation of this improved synchronized_verlet integration method within the LAMMPS framework is detailed, and its effectiveness is validated through a simple three-particle test case and a more general example of granular flow in mixtures with large size-ratios, for which we provide general guidelines for selecting simulation parameters and accurately modeling inelasticity in large particle size-ratio simulations.  more » « less
Award ID(s):
2203703
PAR ID:
10580308
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Computer Physics Communications
Volume:
310
Issue:
C
ISSN:
0010-4655
Page Range / eLocation ID:
109524
Subject(s) / Keyword(s):
Discrete Element Method (DEM) Velocity-Verlet algorithm Granular materials Polydisperse Large size ratio
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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