The influencing factors of nanosecond pulse homogeneous dielectric barrier discharge in air

In this paper, a bipolar nanosecond high pulse voltage with 20 ns rising time was employed to generate homogeneous dielectric barrier discharges using the plate-plate electrode configuration in air at atmospheric pressure. The effects of pulse peak voltage, gas discharge gap, and dielectric plates made by different materials or thicknesses on the discharge homogeneity, voltage-current waveform, and optical emission spectra were investigated. Results show that aforementioned parameters have a strongly impact on the discharge homogeneity and the optical emission spectra, but it is hard to identify definitely their influences on the discharge voltage-current waveform. Homogeneous discharges were easily observed when using low permittivity dielectric plate and the emission intensity of N₂ (C³Π_u → B ³Π_g, 0-0, 337.1 nm) increases with the rising of pulse peak voltage and the permittivity of dielectric material but decreases with the increasing of gas discharge gap and the dielectric plate thickness. The rotational and vibrational temperatures (T_rot and T_vib) were determined at T_rot = 350 ± 5 K and T_vib = 3045 K via fitting the simulative spectra of N₂ (C³Π _u → B³Π_g, 0-2) with the measured one.