Flow Visualization of a Three-Dimensional Wall Jet using the Tuft-Grid Method

This study is to clarify the flow structure of a three-dimensional wall jet discharged on a flat surface from a round nozzle. Instantaneous flow pattern parallel to the wall was visualized by depth-tuft method, and the feature of the large-scale structures existed in the present wall jet was examined. It was revealed that a streak flow pattern corresponding to a ridge pattern of tufts was dominant structure, and that the streaks were generated quasi-periodically. The flow following capability of the tufts was calibrated using a sinusoidally oscillating wind-tunnel.