Abstract:Alternative current (AC) and nanosecond pulse (NS) plasma dielectric barrier discharge (DBD) is applied to the active control of the asymmetrical vortices over the cone of the cone-cylinder. The characteristics of the AC-DBD and NS-DBD is discussed. The experiment is performed in a low speed wind tunnel. The angle of attack is 45? and the wind speed ranges from 5 m/s to 22 m/s. Flow control modes of the actuator are plasma off, port on and starboard on. The result shows that the asymmetrical field can be mirror symmetry control by port on and starboard on of AC-DBD at 5 m/s, but the NS-DBD is not effective. As the wind speed increased, the function of the AC-DBD on asymmetric vortices is gradually disappears, meanwhile the function of NS-DBD is increasing. When the wind speed reaches 22 m/s, NS-DBD can get the asymmetrical field mirror symmetry, but the AC-DBD is not effective. This implies that the NS-DBD is more effective to control the separated vortices field at the higher wind speed relative to the AC-DBD.