Comparison of space and time-resolved electric fields from experiment and simulation in packed bed dielectric barrier discharges*

Packed bed dielectric barrier discharge (PBDBDs) have been extensively investigated for gas conversion applications. Significant past work has been performed using space-resolved modeling. Due to complex geometry, complex chemistry, and atmospheric pressure operation, the models need to rely on several assumptions which influence their accuracy. The improved confidence in model prediction and their utilization requires a quantitative comparison between the experiments and modeling which has been largely missing. In this work, we have compared the 2D electric field, space and time-resolved electron impact excitation and streamer speed in a packed bed plasma reactor operated in helium from both experiments and computations using nonPDPSIM plasma hydrodynamic modeling [1]. The electric field was measured using the helium line ratio method [2] with 2D spatial resolution in an experimental setup pioneered by [3]. The apparent electric field reached values up to 100 kV/cm. The 2D electric fields compare well with the experiments during the surface streamer phase of the discharge and differ for the streamer approach towards the dielectric pellet. The discrepancies have been resolved by changes in the model and/or have been explained based on the limitations of the experimental technique and model.

[1] J Kruszelnicki et al. J. Phys. D: Appl. Phys. 50 025203 (2017)

[2] S.S. Ivković et al. Journal of Physics D: Applied Physics, 47(5): p. 055204 (2014).

[3] J. Čech Plasma Sources Sci. Technol. 27 105002 (2018)