ライブラリ登録: Guest
TSFP DL Home アーカイブ 執行委員会
TSFP DIGITAL LIBRARY ONLINE


ISSN オンライン: 2642-0554

THE IRREGULAR VORTEX SHEDDING REGIME FOR A SQUARE CYLINDER WAKE NEAR A WALL

Sean C.C. Bailey
Advanced Fluid Mechanics Research Group Faculty of Engineering Science, UWO London, Ontario, N6A 5B9, Canada; Department of Mechanical Engineering University of Kentucky Lexington, KY 40506, USA

Gregory A. Kopp
Boundary Layer Wind Tunnel Laboratory and Advanced Fluid Mechanics Research Group Faculty of Engineering Science, University of Western Ontario, London Ontario, N6A 5B9 Canada

Robert J. Martinuzzi
Department of Mechanical and Manufacturing Engineering Schulich School of Engineering, University of Calgary 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4

要約

Surface pressure and wake velocity fluctuations are used to investigate the changes in vortex shedding from a square cylinder near a solid wall for Reynolds number 18,600. Time and frequency analyses show that the formation of shed vortices occurs further downstream of the cylinder as the critical gap height for suppression is approached. Permanent reattachment of the shear layer on the lower cylinder face interrupts the feedback mechanism between the wake and cylinder side face and periodic fluctuations can only be detected downstream of the cylinder. Complete suppression of vortex shedding occurs as the gap height is further reduced. The combined influence of gap blockage and reduced streamline curvature causes a reduction in the ratio of the lower to upper shear layer intensity below the critical value for the stable vortex street formation predicted from stability analysis.