Abstract
This study was focused on vortex structures in a forced rectangular jet. The periodic and alternative disturbance locally excited a pair of major shear layers. The flow visualization was performed by Laser Induced Fluorescence method to grasp 3-D image by stacking the time sequence of cross section images. As a result, the detail of tilting-link structure was observed, and it was revealed that the structure forms only in the excited jet. Mushroom shaped vortex enhances mixing and diffusion in the minor direction of the jet. On the other hand, the jet contraction in major direction is due to the self-induced velocity of the rectangular vortex ring.
