National Aerospace Laboratory
National Aerospace Laboratory
University of Electro-Communications
出版者
航空宇宙技術研究所
出版者(英)
National Aerospace Laboratory (NAL)
雑誌名
航空宇宙技術研究所特別資料: 第28回境界層遷移の解明と制御研究会講演論文集
雑誌名(英)
Special Publication of National Aerospace Laboratory: Proceedings of the 28th NAL Workshops on Investigation and Control of Boundary-Layer Transition
巻
54
ページ
13 - 16
発行年
2002-01
抄録(英)
By-pass transitions triggered by the initial disturbance and the suction/blowing supplied from the bottom wall of the plane Poiseuille flow are directly simulated on a parallel computer. The simulations are started with initial flows given by the basic flow plus small disturbances with different amplitudes for various Reynolds numbers. It is found that when the amplitude of a disturbance is greater than the threshold amplitude, which depends on -1.7 power of the Reynolds number, the by-pass transition of the flow is triggered by the instability of streamwise vortex components in the disturbance. The similar by-pass transitions of the flow are also induced by the stationary suction/blowings supplied from the wall, which seem to simulate a sort of wall surface roughness. When the suction/blowing excites two modes whose streamwise components of wave numbers have an identical magnitude but opposite sign, these modes interact strongly and induce a large streamwise mode which enhances the by-pass transition of the flow, which has been observed as the oblique transition in the experiment.