乱流境界層中の大規模渦構造の解明 : 第1報,発達した人工大規模渦の立体的構造について

概要

論文の詳細を見る
A unique method for an experimental investigation on coherent structures in a turbulent boundary layer is presented. A large-scale coherent vortex was artificially induced by injecting a pair of small pulsative swirling jets into the bottom of a fully-developed turbulent boundary layer. The quantitative inspection for the flow field around the vortex was made on the basis of a simplified conditional sampling method through which the artificial vortex could be easily detected at any fixed location and time. The artificial vortex is proven to have the sculpture of a horse-shoe composed of a pair of vortex tubes inclined downstream. The vortex tubes are joined with each other at the top at about Y/δ=1.2. Its structure resembles that of the natural large-scale coherent 'bulge'. The streamwise, lateral, and spanwise scales of the artificial horse-shoe vortex are about 5δ, 1.4δ, and 2δ, respectively.
社団法人日本機械学会の論文
1989-03-25