Simulation study on influence of oxygen concentrations on atmospheric-pressure streamer in oxygen-rich nitrogen-oxygen mixture

This study aims to investigate the behaviour of positive streamer discharge in various N2/O2 mixtures with different O2 concentrations via two-dimensional simulations. The proposed model considers the effects of photoionisation caused by the photons generated by excited oxygen atoms OI , which enables the simulation of streamers in oxygen rich conditions. The simulation results indicate that the propagation velocity and diameter of the streamer increase with the oxygen concentration, while the emission intensity decreases. The result conforms to the experimental results of our previous work. Moreover, the simulation results suggest that changes in the ionisation rate caused by variations in the oxygen concentration affect the streamer propagation, while the impact of photoionisation is limited.