 |
|
|
Benoît PIER and Patrick HUERRE
LadHyX, École polytechnique - CNRS, 91128 Palaiseau Cedex, France
Journal of Fluids and Structures 15, 471–480 (2001)
The selection criteria governing finite-amplitude synchronized oscillating states are discussed for model systems and real wake flows in a domain of infinite streamwise extent. Two types of nonlinear global modes are possible: hat modes with overall smoothly varying amplitude and elephant modes with a sharp front. The vortex street in wake flows is of elephant type, as observed in direct numerical simulations of a real spatially developing wake. Furthermore, the elephant frequency selection criterion is in excellent agreement with the numerically determined vortex shedding frequency.
hal-00119923
2001c_pier_jfs.pdf