抄録
To control the re-circulating region of an annular jet, we introduced disturbances by means of a gap in the exit end of the nozzle and periodic pressure fluctuations through the nozzle inner body. The effects of these disturbances on the flow structure in the developing region of the jet were investigated by LDV method. Results for the annular nozzle with a fixed outer diameter of 50 mm and exit velocities from 5 to 40 m/s are described.