Abstract
Active control is applied on a circular jet using secondary film flow, with and without acoustic excitation. The velocity ratio of the film flow to the main stream and/or acoustic excitation frequency is changed. This active control method is applied on a circular jet buoyant jet (Carbon dioxide or Helium gas). The jet structure is visualized with laser light sheet in the plane including jet axis. It is described qualitatively the process of vortex ring growth and outbreak that it is generated in the shear layer of jet.
