Study On Improvement Of Dielectric Layer Preparation Process And Strengthening Effect Of Asymmetric Electric Field In DBD

Dielectric barrier discharge (DBD) is an effective way to obtain non-equilibrium plasma at atmospheric pressure or above. Industrial applications of DBD include ozone generation, pollution control, surface treatment, high power CO₂ lasers, UV source, and flat large-area plasma displays. The technology of DBD has a far-reaching development prospects. But the building industrialization plasma source of DBD has a weak foundation in theory, a low dielectric material properties, the system difficult to match, and low efficiency, and many other issues. In order to construct the industrialization plasma source of DBD, this paper combines with "the support projects of science and technology ministry" (No. 2006BAC11B06) and "the talents-support plan of education ministry in new century" (No. NCET-05-0296); two major issues were studied, which involve the preparation of dielectric layer and the strengthening effect of local-space electric field about the construction of industrialized plasma source in DBD.Dielectric constant of enamel is moderate, and enamel has a lower sintering temperature, and has a compact combination of thin electrode plate, has a good heat conductivity and high mechanical robustness ,a good chemical corrosion resistance, it is repairable. But it also has some shortcomings of electrical insulating performance instability at high field and performances dependence on processing parameter. Aiming at these above problems, the preparation process of porcelain enamel is modified as follows: Firstly, twice-annealing is introduced to billet surface treatment technology; Secondly, appropriate sodium chloride is used to suspending agent alcohol is used to diluents while adjusting the concentration of glaze slurry; Thirdly, it is adopted that automatic roll glaze coated lining is based on the traditional manual process in wet; Fourthly, the burning technology is based on low-temperature-burning technology systems and temperature control mode is linear gradient temperature control methods. Through the research of dielectric properties and discharge experiment in DBD, it is proved that the above-mentioned technologic system is the optimal method to product ballasting layer of enamel in DBD.The basic requirement of the plasma source is high-density and high-efficiency for industrial application. While asymmetric electrode can strengthen the space field effectively, and enhance plasma concentration in DBD. Hence, by changing the electrode's shape and radius, we have manufactured three electrode forms of different curvature. There are flat electrode, filamentous electrode and needle electrode. Observing the discharge pattern of DBD, discharge power of DBD, electric field intensity of DBD, I-V characteristics of DBD, discharge waveforms of DBD about three electrode with different curvature, We have gained whether how to change the excitation frequency, the excitation voltage and the discharge gap, With the increase of electrode curvature, the radiation light intensity of micro-discharge has enhanced; Moreover, the power density of DBD increases gradually, and the equivalent electric field strength of DBD also increases gradually; thus, this has proved that DBD electric field strength and power density can be improved effectively by increasing in curvature of the electrodes.