An uniform DBD plasma excited by bipolar nanosecond pulse using wire-cylinder electrode configuration in atmospheric air.

In this study, a bipolar nanosecond pulsed power supply with 15 ns rising time is employed to generate an uniform dielectric barrier discharge using the wire-cylinder electrode configuration in atmospheric air. The images, waveforms of pulse voltage and discharge current, and the optical emission spectra of the discharges are recorded. The rotational and vibrational temperatures of plasma are determined by comparing the simulated spectra with the experimental spectra. The effects of pulse peak voltage, pulse repetition rate and quartz tube diameter on the emission intensities of N2 (C(3)Πu→B(3)Πg, 0-0) and N2(+)B(2)Σu(+)→X(2)Σg(+),0-0 and the rotational and vibrational temperatures have been investigated. It is found that the uniform plasma with low gas temperature can be obtained, and the emission intensities of N2 (C(3)Πu→B(3)Πg, 0-0) and N2(+)B(2)Σu(+)→X(2)Σg(+),0-0 rise with increasing the pulse peak voltage and pulse repetition rate, while decrease as the increase of quartz tube diameter. In addition, under the condition of 28 kV pulse peak voltage, 150 Hz pulse repetition rate and 7 mm quartz tube diameter, the plasma gas temperature is determined to be 330 K. The results also indicate that the plasma gas temperature keep almost constant when increasing the pulse peak voltage and pulse repetition rate but increase with the increase of the quartz tube diameter.