交错电极介质阻挡放电等离子体弦向特性的研究

Investigation of the Characteristics of the Stagger Electrodes Dielectric Barrier Discharge Plasmas in Chord-Wise Direction

在绝缘材料两侧交错布置电极的方式是航空领域所使用的等离子体激励器与众不同之处,因此航空等离子体激励器生成的等离子体具有沿弦向变化特点。利用光谱仪、红外热像仪、激光诱导荧光系统(LIF)对交错电极介质阻挡放电等离子体弦向特性进行了实验研究,并对介质阻挡放电等离子体流动控制机理作了初步的探讨。实验中发现等离子体发光强度和温度沿弦向的分布基本符合高斯分布;发射等离子体光谱强度随着电压升高而增大;等离子体弦向温度随激励电压的增大而增加;通过LIF系统直接检测到放电产生的NO。通过数值模拟得到电极附近的电势和电场强度分布进而对实验现象作了初步的解释,并在以上实验的基础上,将等离子体流动控制机理归纳为撞击效应、温升效应和化学反应效应。

The aerodynamic plasma actuator distinguishes itself from others by a set of highly asymmetric electrodes arranged on dielectric. So the plasma produced by the aerodynamic plasma actuator has special characteristics along chord-wise direction. In the present paper the characteristic of the stagger electrodes dielectric barrier discharge plasmas in chord-wise direction was investigated experimentally through spectrometer, infrared imager and laser induced fluorescence system. The mechanisms behind plasma flow control were discussed briefly based on these experimental results. It was found in the experiments that the distributions of light intensity and temperature in chord-wise direction accord with Gaussian distribution. Light intensity and temperature were enhanced by increasing supplied voltage. NO produced by DBD discharge was detected directly by the LIF system. Through numerical simulations, the distributions of electric potential and electric field near the electrodes were determined and the phenomena observed in experiments were explained. Based on these experimental results, the mechanisms behind plasma flow control were ascertained to be the consequence of collisions, temperature increasing and chemical reactions.