Flow structures of a basic annular jet

This paper describes the modal expansion and conditional sampling results of static pressure fluctuations in the inner and outer mixing regions of a basic annular jet. An understanding of the mechanism of the wake shedding process from the internal recirculating region behind the blunt interface is attempted by conditionally sampled pressure signals. The evolution and characteristics of the shedding wake, wake-induced vortices, and jet vortices in both shear layers are measured and presented. The evolution of the wake-induced vortices in the outer shear layer as a result of excitation by the disturbances associated with the shedding wakes is further supported.