Development of a platform for analyses of ultra-scale direct numerical simulation data of turbulence

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We have performed ultra-scale direct numerical simulations(DNS) of incompressible homogeneous turbulence on the Earth Simulator. The number of grid points is up to 4096^3, the size of which is 64 as large as previous DNS. The attained Taylor micro-scale Reynolds number is as high as 1200. Since the ultra-scale DNS data of turbulence have a potential ability to elucidate high-Reynolds number turbulence, it is desirable to make the data public.In this research, for the purpose of developing a platform for analyses of the ultra-scale DNS data of turbulence, we have made the following studies :(1)We have released the fundamental characteristics as well as the results of various data-analyses of high-Reynolds number turbulence obtained by the ultra-scale DNS. The analyses include those of energy spectrum, pressure spectrum, enstrophy, and dissipation spectra, and the PDF and high-order moments of velocity derivatives in high Reynolds number turbulence. The findings are various new asymptotic properties of these quantities in high-Reynolds number turbulence.(2)We have developed general-purpose programs for the purpose of analyzing the ultra-scale DNS data of turbulence. The programs were written in FORTRAN and MPI. One can analyze the ultra-scale DNS data both on the ES and on the vpp5000/56 system of Information technology center at Nagoya University.(3)We have put the DNS data up to 1024^3 grid points on the Internet (one can download the data from the following URL : http://www.fluid.cse.nagoya-u.ac.jp/~dns/pub/dnsdata/dns.html). We have also made the 2048^3 DNS data available on Information technology center at Nagoya University.(4)We have succeeded on visualizing the ultra-scale turbulence field.(5)We have also performed a large-scale DNS of channel turbulence. The number of grid points is 1024x512x1024 and the attained friction Reynolds number Reτ is 1300.