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We demonstrate similarity-based scaling networks for capacitive radio frequency (RF) plasmas, which extensively correlate discharge characteristics under varied conditions, incorporating the transition from original to similarity states. Based on fully kinetic particle-in-cell simulations, similar RF discharges in argon are demonstrated with three external control parameters (gas pressure, gap distance, and driving frequency) simultaneously tuned. A complete set of scaling pathways regarding fundamental discharge parameters is obtained, from which each plasma state finds its neighboring node with only one control parameter tuned. The results from this study provide a promising strategy for plasma multi-parameter mapping, enabling effective cross-comparisons, prediction, and manipulation of RF discharge plasmas. [ABSTRACT FROM AUTHOR]

To investigate the decomposition law of SF6 under negative direct current partial discharge (PD) at different energies, a SF6 PD hybrid numerical model based on fluid dynamics and plasma chemical reaction models, in which 14 particle species and 24 chemical reactions are considered, is proposed. The effectiveness of the proposed model is validated with the current pulse waveform and the V–I discharge curve obtained by experiment. The influence of discharge energy on SF6 PD characteristic quantities and SF6 decomposition products is investigated with simulation and experiment. The results show that most of the discharge area of SF6 is neutral, and the cation clouds only exist in the ionosphere (4.79–5 mm). With the increase in applied voltage, the electric field intensity of the needle plate gap does not increase completely and even decreases in some areas. Moreover, different from the traditional opinion, the generation of SO2F2 under PD is mainly generated by the hydrolysis reaction of SOF4, which is formed by [SF5], [SF4], and [OH], [O]. The reaction path of [SF2] with O2 is not important. Thus, c(SO2F2)/c(SOF2 + SO2) can be used as the energy characteristic component ratio because of its ability to represent the low-fluorine sulfide ratio n([SF5])/n([SF4]). [ABSTRACT FROM AUTHOR]

The plasma arc caused by lightning overvoltage can significantly degrade the power grid reliability. Thus, it is essential to design an efficient arc extinguishing system. The modeling and analysis of the plasma arc in an arc extinguishing system can provide an essential theoretical basis for improving and optimizing its structure. However, the precision of the governing equation and boundary value of the plasma arc model chosen in previous studies can be entirely different from the corresponding practical values. This study develops an arc extinguishing system named "convective shock wave complex system." In order to further optimize its structure and achieve a better arc extinguishing effect, an appropriate model is established to analyze the plasma's operation characteristics inside the arc extinguishing device while stroking by lightning. Based on the magnetohydrodynamics theory, the COMSOL software is utilized to analyze the temperature of the plasma arc, the flow rate of gas in the cavity, and the conductivity and current density of some monitoring points to comprehensively analyze the plasma's physical characteristics in the system. Finally, a virtual lightning experiment is utilized to evaluate the simulation results. [ABSTRACT FROM AUTHOR]