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Benoît PIER
DAMTP, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
Journal of Fluid Mechanics 458, 407–417 (2002)
In this paper it is shown that the two-dimensional time-periodic vortex shedding régime observed in the cylinder wake at moderate Reynolds numbers may be interpreted as a nonlinear global structure and its naturally selected frequency obtained in the framework of hydrodynamic stability theory. The frequency selection criterion is based on the local absolute frequency curve derived from the unperturbed basic flow fields under the assumption of slow streamwise variations. Although the latter assumption is only approximately fulfilled in the vicinity of the obstacle, the theoretically predicted frequency is in good agreement with direct numerical simulations for Reynolds numbers Re>100.
hal-00120025
2002a_pier_jfm.pdf