Time- and spatially resolved emission spectroscopy of the dielectric barrier discharge for soft ionization sustained by a quasi-sinusoidal high voltage
Time- and spatially resolved emission spectroscopy of the dielectric barrier discharge for soft ionization sustained by a quasi-sinusoidal high voltage
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DOI：
10.1007/s00216-015-8827-7
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发表时间：
2015-06
影响因子：
4.3
通讯作者：
V. Horvatić;A. Michels;N. Ahlmann;G. Jestel;D. Veẑa;C. Vadla;J. Franzke
中科院分区：
文献类型：
--
作者：
V. Horvatić;A. Michels;N. Ahlmann;G. Jestel;D. Veẑa;C. Vadla;J. Franzke
用时间分辨光学发射光谱技术研究了氦毛细管介质阻挡放电，旨在阐明等离子体射流的形成过程。利用706 nm处的氦发射线监测氦原子激发的时空传播。在准正弦高压下持续放电，同时测量了氦原子发射随放电电流的时间演化。研究了整个区域内等离子体沿放电轴的空间发展，包括电极之间的毛细管内位置和毛细管外的等离子体射流。高压电极放置在距离毛细管口2 mm处，地面与高压电极之间的距离为10 mm。氦激发发展的完整时空网格表明，在外加电压的正半周期内，形成了两个独立的等离子体，它们在时间上分开。首先，形成构成等离子体喷流的早期等离子体，随后在毛细管中放电。在早期等离子体中，氦原子的激发传播开始于高压电极附近，并以等离子体射流的形式从毛细管向地电极以及毛细管外几毫米处离开。在早期的等离子体在毛细管和射流中相对缓慢地传播之后，第二个等离子体在电极之间开始。在负电压期间，只有电极之间的毛细管中的等离子体出现。氦激发在氦毛细管DBD中传播的时空演化
A helium capillary dielectric barrier discharge was investigated by means of time-resolved optical emission spectroscopy with the aim of elucidating the process of the formation of the plasma jet. The helium emission line at 706 nm was utilized to monitor spatial and temporal propagation of the excitation of helium atoms. The discharge was sustained with quasi-sinusoidal high voltage, and the temporal evolution of the helium atomic emission was measured simultaneously with the discharge current. The spatial development of the plasma was investigated along the discharge axis in the whole region, which covers the positions in the capillary between the electrodes as well as the plasma jet outside the capillary. The high voltage electrode was placed 2 mm from the capillary orifice, and the distance between the ground and high voltage electrode was 10 mm. The complete spatiotemporal grid of the development of the helium excitation has shown that during the positive half-period of the applied voltage, two independent plasmas, separated in time, are formed. First, the early plasma that constitutes the plasma jet is formed, while the discharge in the capillary follows subsequently. In the early plasma, the helium atom excitation propagation starts in the vicinity of the high voltage electrode and departs from the capillary towards the ground electrode as well as several millimeters outside of the capillary in the form of the plasma jet. After relatively slow propagation of the early plasma in the capillary and the jet, the second plasma starts between the electrodes. During the negative voltage period, only the plasma in the capillary between the electrodes occurs.Graphical AbstractSpatiotemporal evolution of the helium excitation propagation in the He capillary DBD