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On the Formation of a Bead Structure of Spark Channels during a Discharge in Air at Atmospheric Pressure

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On the Formation of a Bead Structure of Spark Channels during a Discharge in Air at Atmospheric Pressure DOI:  https://doi.org/10.30564/jasr.v3i1.1858 Abstract The conditions for the formation of spark channels with a bead structure in an inhomogeneous electric field at different polarities of voltage pulses are studied. Voltage pulses with an amplitude of up to 150 kV and a rise time of ≈1.5 µs were applied across a 45-mm point-to-plane gap. Under these conditions, spark channels consisting of bright and dim regions (bead structure) were observed. It is shown that when current is limited, an increase in the rise time and the gap length does not affect the formation of the bead structure. It was found that an increase in the amplitude of voltage pulses leads to an increase in the length of beads. The appearance of the bead structure is more likely at negative polarity of the pointed electrode. The formation of spark channels was studied with ...

Corona with Streamers in Atmospheric Pressure Air in a Highly Inhomogeneous Electric Field

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Corona with Streamers in Atmospheric Pressure Air in a Highly Inhomogeneous Electric Field DOI:  https://doi.org/10.30564/jasr.v3i4.2342 Abstract The paper presents research data on positive and negative coronas in atmospheric pressure air in a highly inhomogeneous electric field. The data show that irrespective of the polarity of pointed electrodes placed in a high electric field (200 kV/cm), this type of discharge develops via ball streamers even if the gap voltage rises slowly (0.2 kV/ms). The start voltage of first positive streamers, compared to negative ones, is higher and the amplitude and the frequency of their current pulses are much lower: about two times and more than two orders of magnitude, respectively. The higher frequency of current pulses from negative streamers provides higher average currents and larger luminous areas of negative coronas compared to positive ones. Positive and negative cylindrical streamers from a pointed to a plane electrode are detected and suc...

On the Formation of a Bead Structure of Spark Channels during a Discharge in Air at Atmospheric Pressure

Image
On the Formation of a Bead Structure of Spark Channels during a Discharge in Air at Atmospheric Pressure DOI:  https://doi.org/10.30564/jasr.v3i1.1858 Abstract The conditions for the formation of spark channels with a bead structure in an inhomogeneous electric field at different polarities of voltage pulses are studied. Voltage pulses with an amplitude of up to 150 kV and a rise time of ≈1.5 µs were applied across a 45-mm point-to-plane gap. Under these conditions, spark channels consisting of bright and dim regions (bead structure) were observed. It is shown that when current is limited, an increase in the rise time and the gap length does not affect the formation of the bead structure. It was found that an increase in the amplitude of voltage pulses leads to an increase in the length of beads. The appearance of the bead structure is more likely at negative polarity of the pointed electrode. The formation of spark channels was studied with ...

Corona with Streamers in Atmospheric Pressure Air in a Highly Inhomogeneous Electric Field

Image
Corona with Streamers in Atmospheric Pressure Air in a Highly Inhomogeneous Electric Field DOI:  https://doi.org/10.30564/jasr.v3i4.2342 Abstract The paper presents research data on positive and negative coronas in atmospheric pressure air in a highly inhomogeneous electric field. The data show that irrespective of the polarity of pointed electrodes placed in a high electric field (200 kV/cm), this type of discharge develops via ball streamers even if the gap voltage rises slowly (0.2 kV/ms). The start voltage of first positive streamers, compared to negative ones, is higher and the amplitude and the frequency of their current pulses are much lower: about two times and more than two orders of magnitude, respectively. The higher frequency of current pulses from negative streamers provides higher average currents and larger luminous areas of negative coronas compared to positive ones. Positive and negative cylindrical streamers from a pointed to a plane electrode are detected and suc...