摘要
performing experimental measurements and two-dimensional axisymmetric fluid simulations to study coaxial argon dielectric barrier discharge. Oscilloscope measurements capture voltage–charge waveforms and Lissajous figures to resolve cycle-integrated electrical characteristics. Continuous-integration optical emission spectroscopy, though without phase resolution, is used to qualitatively confirm the presence of metastable argon. As the peak voltage increases from 5 kV to 13 kV, the simulated volume-averaged electron temperature exhibits a distinct N-shaped pattern: it reaches a peak at 9 kV, decreases abnormally between 10 kV and 11 kV, and then rises again at higher voltages. This non-monotonic change is due to self-shielding effects caused by dielectric surface charges during the discharge process, as well as power broadening resulting from the spatial expansion of the discharge. The continuous increase in equivalent capacitance indicates the accumulation of surface charges, and the simulated shift of the high-electron-temperature region inward confirms the formation of reverse electric fields induced by these surface charges. The discharge remains in a stable filamentary state under all tested conditions. Since the filaments generated by microdischarge occupy only a small portion of the gap, the volume-averaged electron density calculated from simulations is considerably lower than the peak density within individual discharge streams. This research elucidates the mechanism behind the abnormal drop in electron temperature at moderate voltages and provides insights for controlling atmospheric-pressure dielectric barrier discharge (DBD) phenomena.
