【作者】 朱全华；

【导师】 张芝涛；

【作者基本信息】 大连海事大学 ， 环境科学， 2008， 硕士

【摘要】 DBD是在大气压条件下获得非平衡等离子体的有效方法之一,在等离子体化学、紫外光源、环境工程、高功率气体激光器等许多领域有着广泛的应用,具有深远的发展前景。但目前工业化DBD等离子体源构建中存在理论基础薄弱、电介质材料性能低下、系统难以匹配、效率不高等诸多问题。针对构建工业化DBD等离子体源的需要,本文依托国家科技发展支撑计划项目(编号:2006BAC11B06)与教育部新世纪优秀人才支持计划(NCET-05-0296),对工业化DBD等离子体源构建中涉及的DBD电介质层制备、空间局域电场强化两个主要问题进行研究。搪玻璃的介电常数适中,烧成容易,可以制造的很薄,与金属电极结合紧密,导热性能好,机械强度高,抗化学腐蚀性能优良,可修复,可以作为很好的DBD电介质材料。但要在强电场条件下工作也存在电绝缘性能不稳定,受工艺影响大等缺点。针对上述问题,对DBD镇流层制备工艺进行如下改良:第一,钢坯表面处理工艺引入两次退火处理;第二,调浆时以酒精为稀释剂并加入适当的NaCl为悬浮剂;第三,涂搪工艺采用湿法自动滚釉的涂搪方式;第四,搪烧工艺采用低温长烧制度,具体的温控方式为线性梯度控温方法。通过研究DBD镇流层介电性能和放电实验,证明上述工艺制度为制作DBD镇流层的最优工艺方法。目前工业应用中对等离子体源的基本要求是高密度、高效率。而非对称电极能有效强化DBD空间电场,从而提高DBD等离子体的浓度。为此,通过改变电极形状和曲率半径,构建三种不同曲率的电极形式,分别为平板电极、条形电极和针状电极。观察分析此三种电极形式下的DBD放电斑图、DBD放电功率、电场强度、伏安特性、DBD放电波形得到,无论激励频率、激励电压以及放电间隙如何改变,随着电极曲率的增加,DBD微放电辐射光强逐渐增强:DBD功率密度逐渐增加:DBD等效电场强度逐渐增大;因此说明电极曲率的增加能有效提高放电空间电场强度,提高DBD放电功率密度。更多还原

【Abstract】 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.更多还原