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DOE OSTI · 2429555

NekRS, a GPU-accelerated spectral element Navier–Stokes solver

Fischer, Paul·Kerkemeier, Stefan·Min, Misun·Lan, Yu-Hsiang·Phillips, Malachi·Rathnayake, Thilina·Merzari, Elia·Tomboulides, Ananias·Karakus, Ali·Chalmers, Noel·Warburton, Tim
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Abstract

The development of NekRS, a GPU-oriented thermal-fluids simulation code based on the spectral element method (SEM) is described. For performance portability, the code is based on the open concurrent compute abstraction and leverages scalable developments in the SEM code Nek5000 and in libParanumal, which is a library of high-performance kernels for high-order discretizations and PDE-based miniapps. Critical performance sections of the Navier–Stokes time advancement are addressed. Performance results on several platforms are presented here, including scaling to 27,648 V100s on OLCF Summit, for calculations of up to 60B gridpoints.

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97 MATHEMATICS AND COMPUTINGExascale applicationsGPUIncompressible Navier-StokesNek5000NekRSOCCAPerformanceScalabilitySpectral element methodlibParanumal

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Fischer, Paul, Kerkemeier, Stefan, Min, Misun, Lan, Yu-Hsiang, Phillips, Malachi, Rathnayake, Thilina, Merzari, Elia, Tomboulides, Ananias, Karakus, Ali, Chalmers, Noel, Warburton, Tim. 2022-10-18. NekRS, a GPU-accelerated spectral element Navier–Stokes solver. https://doi.org/10.1016/j.parco.2022.102982

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