A coaxial dielectric barrier discharge plasma-assisted combustion actuator (DBD-PACA) system was set up to study its discharge and optical emission spectrum (OES) characteristics in space in this paper. Results showed that each discharge cycle can be divided into four stages: a, b, c, and d. Discharge-on only occurred in stages b and d. Comparatively, the discharge intensity was larger in stage d due to the memory effect of excited electrons. Moreover, Lissajous figure and current-voltage methods were utilized to calculate the power of the coaxial DBD-PACA, and both methods produced roughly similar results. The power presented an upward trend with increasing input voltage and airflow rate. In addition, numerous second positive system (SPS) excited nitrogen molecules were detected from the OES signals. The intensity of the spectral lines (297.54 nm, 315.76 nm, 336.96 nm, and 357.56 nm) first increased, then maintained, and then increased rapidly with the increased radius; however, the intensity of the spectral lines (380.34 nm, 405.80 nm, and 434.30 nm) basically remained unchanged, then increased, and finally decreased with the increased radius. The vibrational temperature first decreased quickly and then increased and reached the minimum at r = 18 mm with the increased radius. The vibrational temperatures at all collection points decreased with the increased input voltage. However, within the range of 0–280 L/min, when r was lower than 15 mm, the vibrational temperatures first increased rapidly and then decreased slowly; when r was greater than 15 mm, the vibrational temperatures first increased and then basically remained stable.

中文翻译：

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同轴介质阻挡放电等离子体辅助燃烧作动器的放电和发射光谱特性

建立了同轴介质阻挡放电等离子体辅助燃烧执行器（DBD-PACA）系统，研究了其在空间中的放电及光发射谱（OES）特性。结果表明，每个放电周期可分为四个阶段：a，b，c和d。放电仅发生在阶段b和d。相比之下，由于激发电子的记忆效应，d阶段的放电强度更大。此外，利用李沙育图和电流-电压方法来计算同轴DBD-PACA的功率，两种方法产生的结果大致相似。随着输入电压和气流速率的增加，功率呈现上升趋势。此外，从OES信号中检测到许多第二正系统（SPS）激发的氮分子。光谱线的强度（297.54 nm，315.76 nm，336.96 nm和357.56 nm）首先增加，然后保持，然后随着半径的增加而迅速增加；但是，光谱线的强度（380.34 nm，405.80 nm和434.30 nm）基本上保持不变，然后增加，最后随着半径的增加而减小。振动温度首先迅速下降，然后上升并在 半径增加时r = 18 mm。随着输入电压的增加，所有收集点的振动温度均降低。然而，在0-280 L / min的范围内，当r小于15 mm时，振动温度首先迅速升高，然后缓慢降低；然而，当r小于15 mm时，振动温度则迅速升高。当r大于15 mm时，振动温度首先升高，然后基本保持稳定。