Flow Visualization of Superbursts and of the Log-Layer in a DNS at $$ \operatorname{Re} _{\tau } = 950 $$

摘要: This paper uses direct numerical simulations (DNS) of turbulent flow in a channel at \( \operatorname{Re} _{\tau } = 950 \) (Del Alamo, Jimenez, Zandonade, Moser J Fluid Mech 500:135–144, 2004) to provide picture the structures making large contributions Reynolds shear stress. Considerable work this type has been done for viscous wall region smaller \), which log-layer does not exist. Recent PIV measurements velocity fluctuations plane parallel direction have emphasized dominant contribution scale outer flow. prompted Hanratty and Papavassiliou (The role vortices producing turbulence. In: Panton, R.L. (ed) Self-sustaining Mechanism Wall Turbulence. Computational Mechanics Publications, Southampton, pp. 83–108, 1997) use DNS 150,\;300 examine these perpendicular They identified plumes extend from center channel. The data are used explore results further, structure log-layer, test present notions about layer.