A parallel algorithm for the concurrent atomistic-continuum methodology

• Published in: Journal of computational physics Vol. 463; p. 111140
• Main Authors: Diaz, Adrian, Gu, Boyang, Li, Yang, Plimpton, Steven J., McDowell, David L., Chen, Youping
• Format: Journal Article
• Language: English
• Published: Cambridge Elsevier Inc 15.08.2022; Elsevier Science Ltd
• Subjects: Algorithms; Benchmarks; Computational physics; Computer simulation; Concurrent atomistic-continuum method; Crack propagation; Interaction models; LAMMPS; Lead selenides; Molecular dynamics; Nonequilibrium processes; Parallel algorithms; Single crystals; Wave propagation; Concurrent atomistic-continuum method; LAMMPS; Molecular dynamics; Nonequilibrium processes; Parallel algorithms
• ISSN: 0021-9991; 1090-2716
• DOI: 10.1016/j.jcp.2022.111140

•A simulation tool for mesoscale transport processes is demonstrated on LAMMPS.•A multiscale parallel algorithm is devised for a non-local material description.•The CAC algorithm seamlessly couples atomic and continuum descriptions.•CAC extends the predictive power of interatomic potentials to the mesoscale.•CAC simulates the interaction between phonons, defects, and interfaces. In this work we present a parallel algorithm for the Concurrent Atomistic Continuum (CAC) formulation that can be integrated into existing molecular dynamics codes. The CAC methodology is briefly introduced and its parallel implementation in LAMMPS is detailed and then demonstrated through benchmarks that compare CAC simulation results with corresponding all-MD (molecular dynamics) results. The parallel efficiency of the algorithm is demonstrated when simulating systems represented by both atoms and finite elements. The verification benchmarks include dynamic crack propagation and branching in a Si single crystal, wave propagation and scattering in a Si phononic crystal, and phonon transport through the phase interface in a PbTe/PbSe heteroepitaxial system. In each of these benchmarks the CAC algorithm is shown to be in good agreement with MD-only models. This parallel CAC algorithm thus offers one of the first scalable multiscale material simulation methodologies that relies solely on atomic-interaction models.