Abstract:
In order to reveal the flow state dependence of the control effect by alternating current surface dielectric barrier discharge (AC-SDBD) plasma actuation, an array of eight AC-SDBD plasma actuators was designed, and the influence on the flow in the near-wall region was investigated for the mainstream velocity ranging from 20 m/s to 80 m/s. The experimental results show that the array of AC-SDBD plasma actuators can significantly increase the velocity in the near-wall region initially, which eventually drops a bit before finally stabilizes. After the flow reaches a new stable state, the influence range of the plasma actuation can extent as far as 170 mm downstream of the actuators and 10 mm in the wall-normal direction, respectively. Moreover, the velocity distribution near the wall under the plasma actuation depends on the streamwise and wall-normal locations. When the mainstream velocity is small, the plasma actuation increases the near-wall velocity after stabilization, but when the mainstream velocity is above a certain value, the near-wall velocity after the plasma actuation is lower than the corresponding no actuated case.