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On the Development of Turbulent Wakes from Vortex StreetsWake development behind circular cylinders at Reynolds numbers from 40 to 10,000 was investigated in a low-speed wind tunnel. Standard hot-wire techniques were used to study the velocity fluctuations. The Reynolds number range of periodic vortex shedding is divided into two distinct subranges. At r=40 to 150, called the stable range, regular vortex streets are formed and no turbulent velocity fluctuations accompany the periodic formation of vortices. The range r=150 to 300 is a transition range to a regime called the irregular range, in which turbulent velocity fluctuations accompany the periodic formation of vortices. The turbulence is initiated by laminar-turbulent transition in the free layers which spring from the separation points on the cylinder. The transition first occurs in the range r=150 to 300. Spectrum and statistical measurements were made to study the velocity fluctuations.
Document ID
19930092207
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Roshko, Anatol
Date Acquired
September 6, 2013
Publication Date
January 1, 1954
Report/Patent Number
NACA-TR-1191
Accession Number
93R21497
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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