“…The exit shape of the jet is altered in order to passively enhance the threedimensionality of the flow, and thus entrainment and mixing, there have been many efforts devoted to investigating the properties of jets emerging from non-circular nozzles. For example, using a tabbed nozzle generates streamwise vortices in the jet flow, and several studies have reported results for variations in flow field conditions, as well as tab shape, size, number and angle (Ahuja and Brown (9) , Bradbury and Khadem (10) , Samimy et al (11) , Zaman et al (1), (12), (13) , Grinsten et al (14) , Toyoda et al (15) ). In the present work, the interaction between axisymmetric and streamwise vortices in the unexcited and excited coaxial jet was studied experimentally.…”