十分発達したチャネル乱流における大規模流れ構造について(流体工学,流体機械)

概要

論文の詳細を見る
The large-scale flow motions observed at or above the logarithmic layer of fully developed turbulent channel flow were investigated for a Reynolds number of 590 and 1180 defined by the friction velocity and the channel-half width. Large Eddy Simulation was adopted in this study as a numerical tool, considering the fact that sufficiently large analysis region and high Reynolds-number condition were required for the reproduction of the large-scale motions. The structure of the large-scale motions is similar to the fine-scale organized structures in the sense that streamwise velocity fluctuation shows streaky patterns, but their streamwise and spanwise sizes reach about three times and twice as large as the channel-half width respectively. Contrary to the fine-scale organized structures in the vicinity of the wall, these large-scale motions were found to obey the outer-layer scaling, independent of the Reynolds number tested here.
社団法人日本機械学会の論文
2003-04-25