Vol. 12, No.1, pp.22-29 (2018)
Streamer Head Observation in a Wire-Plate Electrode with Varied Wire Electrode Diameters
Y. Nagata1, D. Wang2, and T. Namihira2
1Graduate School of Science and Technology, Kumamoto University, Japan
2Institute of Pulse Power Science, Kumamoto University, Japan
Abstract
Effects of wire electrode diameter on formation and propagation process of streamer discharge in wire-plate electrode in air at atmospheric pressure were investigated using a high speed gated emICCD camera. Wire diameters of 0.2 mm, 1.0 mm and 2.0 mm were used in the study. Pulsed voltages having 100 ns pulse duration and about 90 kV peak voltage, generated by a Blumelein line generator, were applied to the electrodes with a gap fixed at 45 mm. Application of positive pulse voltages to the electrodes caused streamer discharges from wire to plate electrodes. During the streamer discharge, the formation and the propagation of streamer heads were observed. Increasing wire diameters from 0.2 mm to 2.0 mm resulted in the different streamer discharge parameters; propagation velocity of streamer heads from 1.48 mm/ns to 2.14 mm/ns, peak of discharge current from 139.9 A to 161.6 A, number density of streamer discharge reaching the plate electrode from 80 numbers/m to 55 numbers/m, respectively. Also, the streamer head diameter was changed. Therefore, it is concluded that the wire diameter is one of the important parameters to control the characteristics of the pulsed streamer discharge.
Keywords - Pulsed power, streamer discharge, streamer head, wire diameter, wire-plate electrode