On three-dimensional quasiperiodic Floquet instabilities of two-dimensional bluff body wakes
نویسندگان
چکیده
Previous studies dealing with Floquet secondary stability analysis of the wakes of circular and square cross-section cylinders have shown that there are two synchronous instability modes, with long ~mode A! and short ~mode B! spanwise wavelengths. At intermediate wavelengths another mode arises, which reaches criticality at Reynolds numbers higher than modes A or B. Here we concentrate on these intermediate-wave number modes for the wakes of circular and square cylinders. It is found that in both cases these modes possess complex-conjugate pair Floquet multipliers, and can be combined to produce either standing or traveling waves. Both these states are quasiperiodic. © 2003 American Institute of Physics. @DOI: 10.1063/1.1591771#
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