音波により渦輪を周方向に変形させた円形噴流初期領域の渦構造

抄録

Vortex rings are periodically formed in the initial region of a round jet and they change to a wavy shape in the azimuthal direction. It is suggested that this azimuthal deformation is related to streamwise vortexes. In order to investigate the relation between the azimuthal deformation of the vortex ring and the formation of the streamwise vortexes, we attempted to artificially deform the vortex ring in the azimuthal direction by an acoustic excitation. The vortex rings azimuthally deform by introducing a sound wave through the small holes at a nozzle exit, so that the streamwise vortices are constantly generated in the round jet.