https://doi.org/10.1140/epjst/e2016-60334-7
Regular Article
Electric field measurements in an atmospheric-pressure microplasma jet using Stark polarization emission spectroscopy of helium atom
1 State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P.R. China
2 Center for More Electric Aircraft Power System, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016, P.R. China
a e-mail: wushuqun2010@hotmail.com
Received: 17 October 2016
Revised: 12 February 2017
Published online: 3 August 2017
Electric field in an atmospheric-pressure microplasma jet, determined by a non-invasive Stark polarization spectroscopy of He 447.1 nm line, is reported in this work. The microplasma jet was driven by a positive pulsed dc power supply with pulse rising time of 60 ns. First, the electric field strength in the streamer head (Eh) is in the range of 9–17 kV/cm. Second, as the streamer head is shooting out of the tube exit, Eh starts to increase rapidly and then decreases after reaching a maximum of 17 kV/cm, indicating the same tendency of streamer velocity. However, a further analysis reveals that the relationship between the electric field and the streamer velocity is non-linear. Third, although the pulse width plays an important role in the control of the length of plasma plume, it has a minor effect on Eh. Fourth, the electric field strength in the secondary discharge is estimated to be less than 6 kV/cm, which further validates the similarity between the secondary discharge and negative discharge. Finally, over atmospheric-pressure plasmas transferring across the glass tube, the electric field in the head of newborn secondary streamer is about 10 kV/cm.
© EDP Sciences, Springer-Verlag, 2017
