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DOE OSTI · 1832419

Preparing an Incompressible-Flow Fluid Dynamics Code for Exascale-Class Wind Energy Simulations

Mullowney, Paul (ORCID:0000000215045178)·Li, Ruipeng (ORCID:0000000328025763)·Thomas, Stephen·Ananthan, Shreyas·Sharma, Ashesh (ORCID:0000000333379160)·Rood, Jon S. (ORCID:0000000275133225)·Williams, Alan B·Sprague, Michael A. (ORCID:0000000305190379)
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Abstract

The U.S. Department of Energy has identified exascale-class wind farm simulation as critical to wind energy scientific discovery. A primary objective of the ExaWind project is to build high-performance, predictive computational fluid dynamics (CFD) tools that satisfy these modeling needs. GPU accelerators will serve as the computational thoroughbreds of next-generation, exascale-class supercomputers. Here, we report on our efforts in preparing the ExaWind unstructured mesh solver, Nalu-Wind, for exascale-class machines. For computing at this scale, a simple port of the incompressible-flow algorithms to GPUs is insufficient. To achieve high performance, one needs novel algorithms that are application aware, memory efficient, and optimized for the latest-generation GPU devices. The result of our efforts are unstructured-mesh simulations of wind turbines that can effectively leverage thousands of GPUs. In particular, we demonstrate a first-of-its-kind, incompressible-flow simulation using Algebraic Multigrid solvers that strong scales to more than 4000 GPUs on the Summit supercomputer.

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algebraic multigridCFDcomputational linear algebraexascaleGPU computingMATHEMATICS AND COMPUTING,WIND ENERGY

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BibTeXRIS

Mullowney, Paul (ORCID:0000000215045178), Li, Ruipeng (ORCID:0000000328025763), Thomas, Stephen, Ananthan, Shreyas, Sharma, Ashesh (ORCID:0000000333379160), Rood, Jon S. (ORCID:0000000275133225), Williams, Alan B, Sprague, Michael A. (ORCID:0000000305190379). 2021-11-17. Preparing an Incompressible-Flow Fluid Dynamics Code for Exascale-Class Wind Energy Simulations. https://doi.org/10.1145/3458817.3476185

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