Hostname: page-component-848d4c4894-x24gv Total loading time: 0 Render date: 2024-04-30T23:19:45.752Z Has data issue: false hasContentIssue false

Investigation of the flow between a pair of circular cylinders in the flopping regime

Published online by Cambridge University Press:  21 April 2006

H. J. Kim
Affiliation:
NASA Lewis Research Center, Cleveland, OH 44135. USA Present address: Thermal, Fluid and Aeronautical Engineering Research Lab, Korea Advanced Institute of Science and Technology, P.O. Box 131, Cheongrayang, Seoul, Korea.
P. A. Durbin
Affiliation:
NASA Lewis Research Center, Cleveland, OH 44135. USA

Abstract

The wakes of a pair of circular cylinders are grossly unsteady when the cylinders are separated in a direction normal to the approaching flow by less than one cylinder diameter. The wakes flop randomly between two asymmetric states. The time-scale for the flopping is several orders of magnitude longer than the timescale of vortex shedding, and also several orders of magnitude longer than the timescale for instability of the separating shear layers. When a splitter plate is positioned suitably on the centreline of the cylinders, the flopping can be stopped and the flow made to assume either of the asymmetric states, or a symmetric steady state. For a range of plate positions a new, periodic oscillation occurs. Acoustic excitation can also destroy the flopping mean flow, replacing it by a symmetric flow.

Type
Research Article
Copyright
© 1988 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bearman, P. W. & Wadcock, A. J. 1973 J. Fluid Mech. 61, 499.
Bloor, M. S. 1964 J. Fluid Mech. 19, 290.
Foss, J. F. & Korschelt, D. 1983 J. Fluid Mech. 132, 79.
Guckenheimer, J. & Holmes, P. 1983 Nonlinear Oscillations, Dynamical Systems and Bifurcations of Vector Fields. Springer.
Hayashi, M., Sakurai, A. & Ohya, Y. 1983 Trans. Japan Soc. Aero. Space Sci. 26, 22.
Mood, A. M., Graybill, F. A. & Boes, D. C. 1974 Introduction to the Theory of Statistics. McGraw-Hill.
Williamson, C. H. K. 1985 J. Fluid Mech. 159, 1.
Wygnanski, I. & Petersen, R. A. 1985 AIAA paper 85-0539.
Zdravkovich, M. M. 1977 Trans. ASMEI: J. Fluids Eng 99, 618.