The Characterization Of A Mesh-to-Plate Dielectric Barrier Discharge In N₂/O₂Mixtures At Atmospheric Pressure

In this work, the characterization of a mesh-to-plate dielectric barrier discharge in nitrogen, oxygen, air at atmospheric pressure was studied by using the methods of voltage-charge Lissajous figure and optical emission spectrum. The voltage-current waveform and Lissajous figure were measured respectively in nitrogen, oxygen, and air discharge at four given discharge gaps,0.0,0.6,1.1,1.7mm. Breakdown voltage, reduced electric field strength, discharge power, transferred charge were obtained by analyzing Lissajous figure. The simulated figure of N2(C-5,Δv=2) was obtained by using Specair software to get rotational and vibrational temperatures. The change of these discharge parameters with changing discharge voltage in applied gaps and applied gases were discussed. The main results presented in the dissertation have been summarized as follows:At the same discharge gap, with increasing discharge voltage, discharge power is increased linearly, and the increasing rate is related to discharge gap. The transferred charge is also increased linearly and the increasing rate equals to the capacitance of dielectric. The intensity and number of microdischarges, rotational temperature are increased. But breakdown voltage, reduced electric field strength, capacitance of dielectric and gap, vibrational temperature are nearly not changed.At the same discharge voltage, with increasing discharge gap, discharge power, breakdown voltage and rotational temperature are increased. But the capacitance of gap, reduced electric field strength and transferred charge are decreased. The intensity of microdischarges is increased, but the number is decreased.In this research, several discharge parameters of nitrogen, oxygen, air were compared under the given discharge gap and voltage. Due to the electronegative of oxygen, the intensity of microdischarges of air and oxygen are higher than that of nitrogen, but the number of microdischarges of air and oxygen are lower than that of nitrogen. Meanwhile, the transferred charges of oxygen are fewer than that of air and nitrogen due to its high breakdown voltage. Besides, the vibrational temperature of air (3200±100K) is observed to be higher than that of nitrogen (1900±100K), while the rotational temperature of air is found to be slightly higher than that of nitrogen. Generally, the rotational temperature of both ranged from350K to450K when the conditions of discharge are changed.