21019 Vortical Structure in the Wake of Vortex Generator Jets with Asymmetric Jet Orifice Shape

The vortex generator jet method is an active control of flow separation and can achieve the adaptive control by properly adjusting the jet speed. It is important to control flow separation effectively that the details of near fields of the jet are clarified for issuing the jet into a crossflow. For the vortex generator jets, the suppression of flow separation is affected by the jet orifice shape. In particular, the VGJs with asymmetric (T-shaped) jet orifices make effective the separation control in contrast to the VGJs with circular orifices. In this study, structural features resulting from the interaction of an asymmetric jet issuing transversely into a crossflow are described with the flow visualization technique. The formation and behavior of the vortices in the wake were affected by the jet orifice shape. For the T-shaped jet orifice, flow fields in the wake do not indicate the symmetric feature in the spanwise direction, and the wake vortices show the asymmetric structure in the spanwise direction.