Abstract
Peta-Scale Direct Numerical Simulation (DNS) of wall turbulence are conducted by taking advantage of "K Computer". In the previous DNS of turbulent channel flows, Reynolds number based on the friction velocity and the half height of channel, Re_τ, has reached about 2500 owing to developments of supercomputers and numerical algorithms, while bulk Reynolds number, Re_b, is at least hundred thousand, which is corresponds to Re_τ ? 5000, in real thermal and fluid machines in industrial application. In this study, DNS of turbulent channel flows are carried out at high Reynolds number up to Re_τ = 5000 to reveal dynamic interactions between large- and small-scale structures and construct DNS database as the "standard solution" to verify turbulent model calculation in industrial utilization.
