The effect of a Dielectric Barrier Discharge Plasma Actuator (DBD-PA) on the flow characteristics of an annular jet was experimentally investigated. Experiments were conducted at the Reynolds number of 22,000, based on the jet exit velocity; U0 = 5.7 m/s and the nozzle outer diameter; Do = 50 mm. Disturbances from two separate DBD-PAs, attached on the inner surface of the nozzle and on the downstream end surface of the inner cylinder, were introduced into the inner and outer shear layers of the annular jet, and the mean and fluctuating velocity distributions along the jet axis were measured using LDV. The mean stagnation point on the jet axis shifted upstream by PA-driving. This effect was most pronounced when the outer PA was driven at 200 Hz, which is close to the preferred frequency of the inner shear layer of the jet, shortening the axial length of the recirculation region by about half.
ENDO et al. (Wed,) studied this question.