Influence of Pulse Width and Frequency on Discharge Energy and Temperatures in Nanosecond Plasmas

Although nanosecond-pulsed discharges have received increased attention over the last two decades, few studies have examined how modifying the pulse width of the discharge affects the plasma properties. This study employs a plasma-assisted flow tube with a pin-to-pin electrode configuration to understand the impact of pulse width on the discharge energy (measured via voltage and current waveforms) and temperature (measured via optical emission spectroscopy). It is seen that changing the pulse width has dramatic effects on the energy per pulse, breakdown time, and temperature at high pulse repetition frequencies. Longer pulse widths result in discharges with lower energy, longer breakdown times, and reduced heating rates. At lower frequencies, however, the influence of the pulse width is substantially diminished.