This paper investigates the three-dimensional stability of the wake behind a symmetrically confined circular cylinder by a linear stability analysis. Emphasis has been placed on discussing analogies and differences with the unconfined case to highlight the role of the inversion of the von K´arm´an street in the nature of the three-dimensional transition. Indeed, in this flow, the vortices of opposite sign that are alternately shed from the body into the wake cross the symmetry line further downstream and they assume a final configuration which is inverted with respect to the unconfined case. It is shown that the transition to a three-dimensional state has the same space–time symmetries of the unconfined case, although the shape of the linearly unstable modes is affected by the inversion of the wake vortices. A possible interpretation of this result is given here.
|Autori:||CAMARRI S; GIANNETTI F|
|Titolo:||Effect of confinement on three-dimensional stability in the wake of a circular cylinder|
|Anno del prodotto:||2010|
|Digital Object Identifier (DOI):||10.1017/S0022112009992345|
|Appare nelle tipologie:||1.1 Articolo in rivista|