E322 壁乱流の大規模構造について(E-32 乱流渦構造(2),一般講演)

概要

論文の詳細を見る
The large-scale structures observed at or above the logarithmic layer of plane channels are studied using Large Eddy Simulation. We mainly focus on their Reynolds-number scaling in the outer layer and interaction with buffer-layer turbulence. The large structures in the neutral thermal stratification basically obey the outer scaling and their spanwise size is about twice larger than the boundary-layer thickness independent of the Reynolds-number range tested here. On the other hand, they are strongly affected under the thermal stratification and suppressed at a certain weakly stable stratification, contrary to the buffer-layer streaks which is appeared to be rather insensitive to the thermal stratification. Due to their suppression in the outer layer, spectral peak wavelength of the streamwise velocity recovers the linear growth above the buffer layer, which reflects that large-scales are the main reason to prevent the self similarity of the streamwise velocity in wall turbulence.
日本流体力学会の論文
2004-08-09