AM06-12-007 壁乱流フィードバック制御システムにおけるアクチュエータの寸法効果(乱流現象の制御・流れの抵抗低減(2),一般講演)

概要

論文の詳細を見る
Direct numerical simulations of a fully-developed turbulent channel flow with discrete blowing and suction were conducted. Two existing algorithms were tested. The sensitivity of the drag reduction rate to the actuator size strongly depends on the direction; the drag reduction rate is insensitive to the actuator length, while it rapidly drops when the actuator width is increased. When the actuator width is larger than 44 wall units, the position of streamwise vortex relative to the actuator becomes important. Based on the finding, an improved algorithm, which detects the sequence of the streaky structures in spanwise direction, has been proposed. With this algorithm, nearly 10% drag reduction has been achieved when the actuator width is as large as 44 wall units, about the mean spacing of the streaky structures. The present result suggests that the upper limit of the actuator width is the mean spacing of the streaky structures.
日本流体力学会の論文
2006-09-05