https://doi.org/10.1140/epjd/e2010-10258-0
Time-resolved processes in a pulsed electrical discharge in argon bubbles in water
Watching Hills Regional High School, Warren, NJ 108 Stirling Road, 07059, Warren, NJ, USA
Corresponding author: a sgershman@whrhs.org
Received:
6
May
2010
Revised:
7
August
2010
Published online:
10
November
2010
A phenomenological picture of a pulsed electrical discharge in gas bubbles
in water is produced by combining electrical, spectroscopic, and imaging
characterization methods. The discharge is generated by applying 1 
s
pulses of 5 to 20 kV between a needle and a disk electrode submerged in
water. An Ar gas bubble surrounds the tip of the needle electrode. Imaging,
electrical characteristics, and time-resolved optical emission spectroscopic
data suggest a fast streamer propagation mechanism and the formation of a
plasma channel in the bubble. Comparing the electrical and imaging data for
consecutive pulses applied to the bubble at a frequency of 1 Hz indicates
that each discharge proceeds as an entirely new process with no memory of
the previous discharge aside from the presence of long-lived chemical
species, such as ozone and oxygen. Imaging and electrical data show the
presence of two discharge events during each applied voltage pulse, a
forward discharge near the beginning of the applied pulse depositing charge
on the surface of the bubble and a reverse discharge removing the
accumulated charge from the water/gas interface when the applied voltage is
turned off. The pd value of ~300–500 torr cm, the 1 μs long pulse duration, low repetition rate, and unidirectional character of
the applied voltage pulses make the discharge process here unique compared
to the traditional corona or dielectric barrier discharges.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010
