On the passive control of the near-field of coaxial jets by means of vortex shedding

Authors: Örlü, R., Segalini, A. S., Alfredsson, P.H., Talamelli, A.
Document Type: Conference
Pubstate: Published
Journal: 2nd Int. Conf. on Jets, Wakes and Separated Flows, Sept 16-19, 2008, Berlin, Germany
Volume:    1-7
Year: 2008


The present paper confirms experimentally the theoretical result by Talamelli and Gavarini (Flow, Turbul. \& Combust., 2006), who proposed that the wake behind a separation wall between two streams of a coaxial jet creates the condition for an absolute instability. This instability, by means of the induced vortex shedding, provides a continuous forcing mechanism for the control of the flow field. The potential of this passive mechanism as an easy, effective and practical way to control the near-field of interacting shear layers has been demonstrated and its effect towards increased turbulence activity has been shown.