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http://dx.doi.org/10.3795/KSME-B.2003.27.3.357

Characteristics of Near Wake Behind a Circular Cylinder with Serrated fins (IV) - Comparison of Vortex Formation Regions -  

Ryu, Byong-Nam (부산대학교 대학원 기계공학과)
Kim, Kyung-Chun (부산대학교 기계공학부, 기계기술연구소)
Boo, Jung-Sook (부산대학교 기계공학부, 기계기술연구소)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.27, no.3, 2003 , pp. 357-366 More about this Journal
Abstract
An experimental study is performed to investigate characteristics of near of wakes of circular cylinders with serrated fins using a hot-wire anemometer for various freestream velocities. The main focus of this paper is to investigate a reason why a vortex formation length is increased suddenly. Velocity of the fluid which flow through fins decreases as fin's height and freestream velocity increases and fin pitch decreases, and a thickness of boundary layer increases. The finned tube has a lower velocity gradient when the higher boundary layer grows. This velocity gradient on finned tube makes a weak shear force in the wake and moves to downstream in a state of lower momentum transfer between the freestream and the wake. The phenomenon makes a vortex formation length increased suddenly. The fluctuations of the velocity distributions on the finned tube and (equation omitted) = 1.0 contour line in the vortex formation region decreases when the fin height increases and the pitch decreases.
Keywords
Vortex Formation Length; Phase Average; Integral Length Scale; Serrated Fin Tube;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
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