Showing papers by "Steven J. Plimpton published in 2021"
TL;DR: The Exascale Computing Project (ECP) is invested in co-design to assure that key applications are ready for exascale computing as discussed by the authors, and the Co-design Center for Particle Applications (CoPA) is established within ECP.
Abstract: The Exascale Computing Project (ECP) is invested in co-design to assure that key applications are ready for exascale computing. Within ECP, the Co-design Center for Particle Applications (CoPA) is ...
17 citations
TL;DR: The Co-design Center for Particle Applications (CoPA) as discussed by the authors is addressing challenges faced by particle-based applications across four sub-motifs: short-range particle-particle interactions (e.g., those which often dominate molecular dynamics (MD) and smoothed particle hydrodynamics (SPH) methods), long-range PIC methods, and linear-scaling electronic structure and quantum molecular dynamics algorithms.
Abstract: The Exascale Computing Project (ECP) is invested in co-design to assure that key applications are ready for exascale computing. Within ECP, the Co-design Center for Particle Applications (CoPA) is addressing challenges faced by particle-based applications across four sub-motifs: short-range particle-particle interactions (e.g., those which often dominate molecular dynamics (MD) and smoothed particle hydrodynamics (SPH) methods), long-range particle-particle interactions (e.g., electrostatic MD and gravitational N-body), particle-in-cell (PIC) methods, and linear-scaling electronic structure and quantum molecular dynamics (QMD) algorithms. Our crosscutting co-designed technologies fall into two categories: proxy applications (or apps) and libraries. Proxy apps are vehicles used to evaluate the viability of incorporating various types of algorithms, data structures, and architecture-specific optimizations and the associated trade-offs; examples include ExaMiniMD, CabanaMD, CabanaPIC, and ExaSP2. Libraries are modular instantiations that multiple applications can utilize or be built upon; CoPA has developed the Cabana particle library, PROGRESS/BML libraries for QMD, and the SWFFT and fftMPI parallel FFT libraries. Success is measured by identifiable lessons learned that are translated either directly into parent production application codes or into libraries, with demonstrated performance and/or productivity improvement. The libraries and their use in CoPA's ECP application partner codes are also addressed.
14 citations
11 Jan 2021
TL;DR: In this paper, a compressible Taylor-Green vortex flow is simulated using both non-continuum molecular gas dynamics and continuum computational fluid dynamics, showing that molecular-level fluctuations break the flow symmetries and thereby produce different but statistically similar routes from the initial nonturbulent flow to the long-time turbulent flow.
Abstract: For high-Mach-number turbulent flows, the Kolmogorov length scale can be comparable to the gas-molecule mean-free path, which could introduce noncontinuum molecular-level effects into the turbulent energy cascade. To investigate this issue, compressible Taylor-Green vortex flow is simulated using both noncontinuum molecular gas dynamics and continuum computational fluid dynamics. Although the energy-decay rates are the same, molecular-level fluctuations break the flow symmetries and thereby produce different but statistically similar routes from the initial nonturbulent flow to the long-time turbulent flow.
13 citations
TL;DR: This work describes how rendezvous algorithms work in a scientific computing context and gives specific examples for molecular dynamics and Direct Simulation Monte Carlo codes which result in dramatic performance improvements versus simpler algorithms which do not scale as well.
4 citations