On the propagation of the pressure fluctuations in turbulent channels at high Reynolds numbers

Abstract

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.