双极性等离子体激励器圆柱绕流控制实验研究

在低速风洞中利用多级双极性等离子体激励器控制圆柱绕流的流动分离。实验风速U∞=10m/s,基于圆柱直径的雷诺数Re=2.8×10^4,在实验中将两组三级双极性等离子体激励器布置在圆柱模型肩部,利用粒子图像测速技术测量圆柱的尾流场。实验结果表明,采用定常和非定常激励均能抑制圆柱尾迹区,等离子体激励强度是影响激励器对圆柱绕流控制能力的重要因素;非定常脉冲激励耗电少,对流动控制能力强,效率明显高于定常激励,脉冲激励频率影响等离子体激励器对流动的控制能力。在实验风速为10m/s时,脉冲激励频率与圆柱涡脱落频率一致,流动控制效果较好。

Flow control on a circular cylinder using multi-bipolar plasma actuator

A new designed multi-bipolar dielectric barrier discharge actuator was reported for controlling flow separation from a circular cylinder in cross-flow. This new type plasma actuator was adopted with the electrode of former covered electrode and later exposed electrode connected together. We used this new designed actuator to control flow separation of a circular cylinder in cross-flow. The experiment was performed in a low speed wind tunnel at Re=2.8×10^4. The near wake structure of a circular cylinder was studied using particle image velocimetry （PIV）. It was shown that the flow separation was suppressed when the plasma actuators were activated either in steady mode or in unsteady pulsed mode. The strength of the actuation was an important factor for the control of flow separation. Interestingly, with this multi-bipolar dielectric barrier discharge actuator, we found the pulsed actuation frequency of StD：0. 21 was more effective for the flow separation control in the case of unsteady plasma actuation