RELAMINARIZATION MECHANISM IN TURBULENTCHANNEL FLOW BY STREAMWISE TRAVELING WAVE-LIKE BLOWING AND SUCTION

Hiroya Mamori
Department of Mechanical Engineering, Keio University, Hiyoshi 3-14-1, Kohoku-ku, Yokohama 223-8522,Japan; Department of Mechanical Systems Engineering Tokyo University of Agriculture and Technology 2-24-16 Koganei City Naka Town Tokyo; Tokyo University of Science,6-3-1 Niijuku, Katsushika-ku, Tokyo, 125-8585, Japan

Kaoru Iwamoto
Department of Mechanical Engineering, Tokyo University of Science, Noda-shi, Chiba 278-8510; Department of Mechanical System Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588, Japan

Akira Murata
Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588, Japan

Abstrakt

Direct numerical simulation of fully developed channel flow under controlled by traveling wave-like blowing and suction is presented. Similar to a result in traveling wave-like wall deformation, a transition from a turbulent flow into a laminar flow due to downstream traveling wave is found. According to the visualization of the flow field, the negative Reynolds shear stress appears (it is ordinary positive) and develops with time advance, then a turbulent fluctuation disappears.