Experimental study of flow acceleration using plasma actuator of multi-bipolar electrodes

Dielectric barrier discharge (DBD) plasma actuators can be used in flow control applications due to the momentum transfer from plasma to fluid. Due to geometry limitation, however, only small trust can be obtained by DBD plasma actuators, which limits its application in large-scale flow problems. Usually, several surface DBDs are combined in series to obtain a single multistage actuation surface. However, the mutual interaction between successive discharges limits the effectiveness of such multi-DBD actuators. In this paper, a new multi-bipolar DBD plasma actuator is proposed for large-scale flow control applications. An innovative method for constructing multiple plasma actuators of bipolar electrodes is introduced to enhance the thrust. Multi-bipolar electrodes are adopted with the electrode of former covered electrode and later exposed electrode connected together. To validate the proposed method, particle image velocimetry (PIV) experiments are performed. The results show that cross-talk phenomenon can be reduced greatly and thus a constantly accelerating electric wind velocity can be obtained above the multi-bipolar actuator. It is concluded that compare to traditional actuators the new configuration can increase the thrust significantly.