新型介质阻挡放电等离子体激励器的放电与诱导流动特性实验

等离子体流动控制扩大压气机稳定性对等离子体激励器的诱导气流速度提出了更高的要求。进行了新型布局介质阻挡放电等离子体激励器的放电特性与诱导流动特性研究,实验研究不同放电电压和占空比对激励器诱导气流速度的影响,并与传统布局激励器进行了对比分析,探讨其在压气机扩稳实验上应用的可能性。结果表明:相对于传统布局等离子体激励器一个放电周期内有一次"强"放电和一次"弱"放电,新型布局等离子体激励器有两次"强"放电;放电频率为15k Hz时,新型布局激励器的诱导气流速度在较低电压下比传统布局激励器小,在较高电压下比传统布局激励器大,最大速度能达到4.7m/s,因此在高电压下能够更好地抑制压气机叶顶泄露流或泄露涡的流动;两种激励器产生的射流都为紊流,随电压增高诱导气流紊流度增大,且新型布局激励器在高电压下紊流度更大,能更好地促进压气机主流与附面层之间的掺混;固定放电电压和放电频率,两种激励器的诱导气流速度均随着占空比增大而线性增大。

Experimental Research on the Discharge and Induced Flow Characteristics of a New Dielectric Barrier Discharge Plasma Actuator

Improving the stability of compressor with plasma flow control required higher induced flow velocity produced by plasma actuator. This paper carried out related experiments to study the electrical and induced flow characteristics by new dielectric barrier discharge (DBD) plasma actuator. Moreover, the effects of the different discharge voltage amplitudes and duty cycles on the induced flow velocity of the new DBD actuator were analyzed. Compared with the characteristics of the traditional DBD actuator, the possibility for improving the stability of compressor was also discussed. The results show that, the traditional DBD actuator has one strong and one weak discharges in one discharge cycle, but the new DBD actuator has two strong discharges. When the discharge frequency is 15kHz, the induced flow velocity of the new DBD actuator is smaller than that of the traditional DBD actuator under low voltage, while it is bigger under high voltage. The maximum induced flow velocity of the new DBD actuator can increase to 4.7m/s, so the flow of compressor can be better controlled. Both induced flows produced by two actuators are turbulent flow. The turbulence of induced flow rises with the increase of voltage, and the turbulence of new DBD actuator is stronger at high voltage.Therefore it can promote the mixing between the main flow and boundary layer. With the fixed discharge voltage amplitude and frequency, the induced flow velocities of the two types of DBD actuator ascend linearly with the increase of cycle duty.