Application of nanosecond pulsed dielectric barrier discharge for sooty surface regeneration

In this paper, the regeneration of sooty surface by using nanosecond pulsed surface dielectric barrier discharge type reactor is investigated experimentally. The reactor is composed of two electrodes separated by a dielectric and arranged asymmetrically. The power supply system provides high voltage pulses with the following characteristics: voltage up to ±10 kV, rise and decay times less than 50 ns and a frequency of 2 kHz. The main results show that the regeneration performance increases with the applied voltage magnitude and the duration of treatment. Furthermore, depending on the polarity and the magnitude of the applied voltage pulse, the regenerated surface shape could be more uniform along the active electrode (negative pulses) or more extended on the dielectric surface (positive pulses). The regeneration mechanism remains not very well understood, but it seems that the soot particle size is reduced mainly due to the interaction with ozone molecules and oxygen radicals generated by the discharge.