Speaker
Tao Shao
(Institute of Electrical Engineering, Chinese Academy of Science)
Description
Nanosecond pulse discharges in air and other gases at atmospheric pressure can behave various forms of discharges, such as corona, diffuse, spark or arc. In this paper, characteristics of three typical nanosecond pulse discharges, including diffuse discharges, gliding discharges and synthetic jet, in an inhomogeneous electric field are presented.
Diffuse discharges can be obtained at atmospheric pressure with high pulse repetition rate in a point-to-plate. It can be identified as an intermediate state between corona and spark streamer discharges in an inhomogeneous electric field. The corresponding conduction current was unipolar and had amplitude of several amperes, which had the similar amplitude with the displacement current. Furthermore, discharge area of diffuse discharges could be increased by using a multi-needles-plate electrode configuration, a coaxial electrode configuration with a diameter of 5 cm or a knife-plate electrode configuration with an axial length of 30 cm.
Gliding discharges are created in pin-to-pin or a hollow electrodes atmospheric pressure with an air flow. A non-stable stage would appear some time after the discharge go into the stable stage, in which the gliding discharges transitioned from repetitive sparks to diffuse discharges. Furthermore, high flow rate will lead to the spark-to-diffuse transition in pin-to-pin electrodes, and the repetitive sparks are more likely to obtain at high repetition rate, which is benefit to the applications for ignition and combustion. In addition, evolution of the nanosecond-pulse gliding discharges is observed by using a high-speed camera.
Plasma synthetic jet is exited by a home-made pulsed generator in pin-to-pin electrodes. The breakdown voltages for different discharge capacitors keep the same when the gap is fixed. Furthermore, large discharge current can be produced when the discharge capacitor is used. The discharge current increases with the value of the discharge capacitor. The ratio of dissipation energy is higher in the case with discharge capacitor than that in the case without discharge capacitor.
Author
Tao Shao
(Institute of Electrical Engineering, Chinese Academy of Science)
Co-authors
Dr
Cheng Zhang
(Institute of Electrical Engineering, Chinese Academy of Science)
Ms
Chengyan Ren
(Institute of Electrical Engineering, Chinese Academy of Science)
Dr
Ruixue Wang
(Institute of Electrical Engineering, Chinese Academy of Science)
