Abstract: Mixing of a subsonic exhaust plume from a nozzle is induced and enhanced, and shaping of the plume is controlled, by periodic pulsed jets of fluid injected into the plume from two or more locations spaced circumferentially about the plume. The jets are pulsed out of phase relative to one another. An active flow control apparatus includes at least first and second pulsed jet nozzles circumferentially spaced apart about the exhaust plume near an exit plane of the exhaust nozzle, and a pulse generator operable to supply periodic pulses of fluid to each of the pulsed jet nozzles such that the pulses to each nozzle are out of phase relative to the pulses to the other nozzle or nozzles.