高レイノルズ数における乱流チャネル内の圧力変動の伝播

抄録

The propagation of the pressure fluctuations in turbulent channel flows is analyzed using direct numerical simulation up to Reynolds number of 2000, based on the channel half-depth h, friction velocity u^τ, and kinematic viscosity ν. It was found that the convection velocity of the pressure field is consistent with the local mean velocity above the wall-normal height of y⁺ ≈ 20 (y⁺ = yu_τ/ν). Below y⁺ ≈ 20, the convection velocity is invariant and equals the local mean velocity at y⁺ ≈ 20.