Analyses of extreme-scale turbulence datasets in short simulations of forced isotropic turbulence enabled by exascale computing*

Access to the world's first exascale computer (named Frontier) combined with a protocol of multiple independent simulation segments at high resolution [Phys.  Rev. Fluids 2020, 110517] have led to the creation of a new DNS data collection of isotropic turbulence at the scale of 32768-cubed grid points. Advances in GPU computing techniques [paper in review]  have also greatly facilitated both on-the-fly processing on a time-resolved basis, and the memory-intensive post-processing of single-time snapshots of size at 1/4 of a petabyte or larger.  We will discuss intermittency corrections for energy spectra and velocity structure functions, as well as the behavior of cumulative distribution functions that quantify the likelihood of extreme events present in both pointwise and locally-averaged fluctuations of the energy dissipation and enstrophy. Attention is given to both dissipation-range and inertial-range phenomena.