“…The radial grid width is distributed so that the region near the pipe wall has the highest resolution. This resolution is verified in the aspect of radial distributions of the first and Mitsuishi, Takahashi, Shimura, Iwamoto and Murata, Journal of Thermal Science and Technology, Vol.16, No.1 (2021) second moments of turbulent statistics in the previous DNS with the periodic boundary condition in the axial direction (Mitsuishi et al, 2020).…”