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Title: Modernization and optimization of a legacy open-source CFD code for high-performance computing architectures

Legacy codes remain a crucial element of today's simulation-based engineering ecosystem due to the extensive validation process and investment in such software. The rapid evolution of high-performance computing architectures necessitates the modernization of these codes. One approach to modernization is a complete overhaul of the code. However, this could require extensive investments, such as rewriting in modern languages, new data constructs, etc., which will necessitate systematic verification and validation to re-establish the credibility of the computational models. The current study advocates using a more incremental approach and is a culmination of several modernization efforts of the legacy code MFIX, which is an open-source computational fluid dynamics code that has evolved over several decades, widely used in multiphase flows and still being developed by the National Energy Technology Laboratory. Two different modernization approaches,‘bottom-up’ and ‘top-down’, are illustrated. Here, preliminary results show up to 8.5x improvement at the selected kernel level with the first approach, and up to 50% improvement in total simulated time with the latter were achieved for the demonstration cases and target HPC systems employed.
 [1] ;  [2] ;  [3] ;  [4]
  1. ALPEMI Consulting LLC, Phoenix, AZ (United States)
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
  3. Intel Corp., Chandler, AZ (United States)
  4. Intel Corp., Novosibirsk (Russia)
Publication Date:
Report Number(s):
Journal ID: ISSN 1061-8562; 655038
Grant/Contract Number:
Accepted Manuscript
Journal Name:
International Journal of Computational Fluid Dynamics
Additional Journal Information:
Journal Volume: 31; Journal Issue: 2; Journal ID: ISSN 1061-8562
Taylor & Francis
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
97 MATHEMATICS AND COMPUTING; computational fluid dynamics (CFD); MFIX; reacting multiphase flow simulations; legacy software; code modernization; code refactoring; trilinos project; high-performance computing; many cores; xeon phi
OSTI Identifier: