宽气压下介质阻挡放电等离子体激励器放电特性

Discharge Characteristics of Dielectric Barrier Discharge Plasma Actuator at Broad Pressure Range

为适应飞行器在高空宽气压环境下的等离子体流动控制,基于典型构型的介质阻挡放电等离子体激励器(dielectric barrier discharge plasma actuator,DBDPA)在不同气压下的静止大气放电实验,研究了气压对DBDPA放电的起始放电电压、辉光形态、光谱特性、伏安特性、放电功率、诱导气流的时均反推力和时均速度等的影响特性。研究结果表明:随着气压的逐渐下降(从0.1 MPa降至0.02 MPa),DBDPA的起始放电电压逐渐降低(从6.4kV降至2.8 kV),放电辉光逐渐增强,辉光区域逐渐变大(从约2 mm增到15 mm);光谱特征谱线位置不变,光谱强度增加;电流幅值和微放电电流脉冲逐渐增强;放电功率单调增加,并在0.06 MPa以下阶段呈现陡增;诱导气流的时均速度整体上单调增加;而时均反推力先增加后减少,存在峰值气压,随着驱动电压峰值从12 kV增加至16 kV,峰值气压从0.04 MPa增至0.06 MPa。另外,诱导气流的时均反推力和时均速度与驱动电压和频率均成正比。在特定的低气压0.05 MPa下,DBDPA的放电功率与驱动电压成正比,而随着驱动频率的增加,放电功率先增加后减少,存在峰值频率3.5 kHz。

In order to adopt to the broad pressure range of aircraft at high attitude under plasma flow control, based on the classical dielectric barrier discharge plasma actuator(DBDPA) and its discharge in different pressure in stationary atmospheric, we investigated the influences of pressure on the discharge onset voltage, glow pattern, spectral characteristics,V-A characteristics, discharge power, time averaged thrust, and time averaged velocity of induced flow. The results show that, as the air pressure drops from 0.1 MPa to 0.02 MPa, the onset voltage decreases gradually from 6.4 kV to 2.8 kV, the discharge glow becomes brighter and its area becomes wider(from about 2 mm to 15 mm), and the spectral intensity increases;the line position remains unchanged, the current amplitude and the peak of micro-discharge current pulseincreases;the discharge power increases monotonically and raises steeply below 0.06 MPa, the time averaged velocity of induced flow increases monotonically on the whole, while the time averaged thrust firstly increases and then declines, where a peak-value pressure exists in proportional to the driven voltage, 0.04 MPa for 12 kV and 0.06 MPa for16 kV. In addition, both of the two time averaged quantities, thrust and induced velocity, are proportional to the driven voltage and frequency respectively. At a particular low atmosphere pressure, 0.05 MPa, the discharge power is proportional to the driven voltage, but increases first and then decreases as the frequency rincreases, where a peak-value frequency of 3.5 kHz exists.