Self-pulsing discharges in pre-heated air at atmospheric pressure

Abstract

The paper presents investigations of self-pulsing discharges in atmospheric pressure air preheated to 300-1000 K. Despite using a direct-current power supply, two self-pulsing discharge regimes, a repetitive transient spark (TS) and a repetitive streamer (RS) were generated. The pulse repetition frequency, on the order of a few kHz, can be controlled by adjusting the generator voltage. The TS is a discharge initiated by a streamer, followed by a short (tens of ns) spark current pulse (∼ 1 A), associated with the total discharging of the internal capacity of the electric circuit. The TS is suitable for the study of 'memory' effects (pre-heating, preionization) on the mechanisms of streamer-to-spark transition and electrical breakdown in atmospheric pressure air. The TS regime was stable below ∼600 K. Above ∼600 K, a stable repetitive streamer (RS) regime was observed. In this regime, the breakdown and spark did not occur. After the initial streamer, the internal capacity of the electrical circuit discharged partially. With further pre-heating of the gas, the stable TS appeared again at ∼1000 K.

Specificity of detection methods of nitrites and ozone in aqueous solutions activated by air plasma

“…A DC‐driven TS discharge in positive polarity was generated in point‐to‐plane configuration in ambient air at atmospheric pressure. TS discharge is a self‐pulsing repetitive streamer‐to‐spark discharge with very short duration (<50 ns) of spark current pulse (∼20–30 A) with the typical repetitive frequency ∼1 kHz and has been studied and described in detail in . The reactor consisted of the high voltage (HV) hollow needle electrode which allowed for the injection of the aqueous solutions with the constant flow rate 0.5 mL min −1 by the syringe pump Pump Systems NE‐300 directly through the active discharge zone.…”

Atmospheric‐pressure pulsed discharges and plasmas: mechanism, characteristics and applications

“…For example, they observed the first and second discharge processes and obtained the OH density (10 14 cm −3 ) by ICCD. Laux et al [26][27][28] studied the nanosecond discharge modes in a pin-to-pin gap structure and their application for combustion by experiments and simulation. Three typical discharges were found: corona, glow and spark discharges.…”

Filamentary nanosecond surface dielectric barrier discharge. Plasma properties in the filaments

“…Nanosecond repetitive pulsed discharge (NRPD) [8] was suggested as an efficient tool for plasma-assisted combustion. Different discharge regimes, depending on the gas temperature, the flow rate, the gap between the electrodes and the mean discharge current were studied [9]. Extra-high electron densities, up to n e = 4 • 10 18 cm −3 , were obtained from Stark broadening in pure N 2 and in the N 2 :H 2 O mixture in nanosecond repetitive pulsed discharge initiated by a 170 ns 1 kHz voltage pulse in 2 mm pin-to-pin gap [10].…”