Numerical investigation of trichel pulse of negative corona discharge in N₂–O₂mixture

Abstract

Trichel pulse of negative corona discharge in atmospheric air is investigated numerically using a 2D fluid model. The model consists of a hyperbolic cathode tip and a plane anode, and considers 11 kinds of particles and the most important interactions among them. The spatio-temporal evolution of charged species and the electric field are evaluated during the pulse process. During the pulse rising edge, the positive ions accumulate ahead of the tip forming the temporal cathode sheath, significantly enhancing the local field. In the pulse decay edge, the temporal sheath collapses and the discharge falls back to a low-current mode. In the pulse interval, the discharge does not cease but sustains weakly until the next pulse. The location of the temporal sheath is independent of the averaged value during the Trichel pulse regime and also the same with that in a normal glow regime, which determines a nearly constant pulse rising time at given configurations. However, a smaller tip radius will lead to their decrease. The effect of negative ions on the pulse process is studied by adjusting the attachment rates. It indicates that the negative ions are actually not necessary in the Trichel pulse process, but will influence the pulse waveform significantly.

Numerical study of the self-pulsing of DC discharge: from corona to parallel-plate configurations

“…Since the recombination coefficient, diffusion coefficient and ion mobility are set as constants in the model, then the decay of the pulse should be mainly determined by the electric field, which relates to the space charges. As seen in figure 12, the rising time increases with the radius of cathode curvature, which is in agreement with the previous results [11,17,18,24,32]. However, the pulse rising time remains nearly unchanged with the discharge current increasing.…”

“…They found that adding oxygen to the above gases increased the voltage range at which Trichel pulses appear. The team further performed numerical simulations of this phenomenon and found that Trichel pulses could be reproduced when the production rate of negative ions was set to 100%, 1% and 0 [18]. Negative ions indeed affect the pulse amplitude and pulse decay edge, but are not necessary for pulse formation.…”

“…Akishev et al [14] observed Trichel pulses in nitrogen and suggested that the behavior of a positive ion cloud near the cathode provides an explanation for the pulse formation. Ouyang's group [15][16][17][18] observed Trichel pulse trains in argon and nitrogen and measured the current-voltage (V-I) curve of the discharge cell under various pressures. Their results suggested the decisive role of positive ions in Trichel pulse formation.…”

Review on ionization and quenching mechanisms of Trichel pulse*

“…3. Many twodimensional (2D) fluid models that were built to simulate the whole process of Trichel pulse successfully [31][32][33][34][35][36][37][38] only considered ISEE as the feedback mechanism. The flux of ISEE (Γ e ) is easy to calculate in the fluid models and determined by…”

“…On the other hand, quenching and regenerating of regular pulses are dominated by negative ions in electronegative gases, which is generally well accepted. [30][31][32][33][34][35][36][37][38] However, the pulsed mode has been reported in non-electronegative gases [40][41][42][43][44][45] which challenges the role of negative ions. In this review, we summarize the pulsed mode in non-electronegative gases (whether this mode can be called as Trichel pulse is still not conclusive) since we can get a comprehensive understanding of quenching mechanism through the comparison.…”