Ultrascale Simulations of Non-smooth Granular Dynamics

TL;DR

This paper introduces scalable algorithms for massively parallel granular dynamics simulations on distributed systems, enabling the simulation of up to ten billion non-spherical particles with high efficiency.

Contribution

It presents novel parallel algorithms and a domain partitioning approach that significantly improve scalability and robustness for large-scale granular simulations.

Findings

Achieved excellent strong and weak scaling on supercomputers

Simulated up to ten billion particles and contacts

Demonstrated robustness on peta-scale clusters

Abstract

This article presents new algorithms for massively parallel granular dynamics simulations on distributed memory architectures using a domain partitioning approach. Collisions are modelled with hard contacts in order to hide their micro-dynamics and thus to extend the time and length scales that can be simulated. The multi-contact problem is solved using a non-linear block Gauss-Seidel method that is conforming to the subdomain structure. The parallel algorithms employ a sophisticated protocol between processors that delegate algorithmic tasks such as contact treatment and position integration uniquely and robustly to the processors. Communication overhead is minimized through aggressive message aggregation, leading to excellent strong and weak scaling. The robustness and scalability is assessed on three clusters including two peta-scale supercomputers with up to 458752 processor cores. The simulations can reach unprecedented resolution of up to ten billion non-spherical particles and contacts.