Evolution of Surface Dielectric Barrier Discharge Driven by Nanosecond Pulses with High Repetition Rates

The pulse repetition frequency (PRF) was demonstrated to significantly affect the discharge physics in nanosecond-pulse surface dielectric barrier discharge (NS-SDBD), showing nonlinear evolution characteristics and modulation effects. Previous research was mainly limited to frequencies below 5 kHz, leaving higher PRF regimes insufficiently explored. In this study, the experimental range was extended to 5-50 kHz. A clear frequency dependence of secondary ionization waves was observed, corresponding to three distinct discharge modes: (1) a discrete-channel mode dominated by surface ionization waves (SIWs) at 5-16 kHz, (2) a transition mode mode at 20-30 kHz, (3) a filamentary mode with streamer dominance (Streamer>SIW) at 35-50 kHz. These findings were verified through ICCD and high-speed imaging, which captured the propagation behavior of SIWs and streamers during the initial nanoseconds of discharge. In addition, The deposited energy was found to correlate strongly with both PRF and pulse number. In the discrete-channel mode (5-16 kHz), rapid energy saturation was observed. The transitional region (20-30 kHz) exhibited dual-mode energy characteristics, while the filamentary mode (35-50 kHz) showed fast energy peaking followed by rapid decay, occasionally leading to thermal runaway. This work provides important theoretical guidance and design principles for high-PRF NS-SDBD applications in engineering fields.