Abstract
Active control of a rectangular jet has been attempted to manipulate the vortex shedding interval in the major shear layer. It is considered essential that the vortex distribution along the each major shear layers plays an important role to characterize a rectangular jet behavior. In the present investigation, it was remarkably observed that the jet spreads more widely in the minor direction and contracts more greatly in major direction by the asymmetric excitation than that of the non-excited jet. The measurement results showed that the coherent vortices are generated in synchronization with the excitation frequency and the pattern. In addition, it was revealed that the inclined vortex rings are formed and interacted with each other only when the jet was excited by asymmetric mode.The jet spreading is attributed to the tilting alignment of the vortex ring, and the jet contracting in minor direction is due to the self-induced deformation of the rectangular vortex ring.
