【作者】 李永辉；

【导师】 董丽芳；

【作者基本信息】 河北大学 ， 光学， 2007， 硕士

【摘要】 利用特殊设计的水电极介质阻挡放电装置,通过先升高电压使气体击穿然后逐渐降低电压的方法(清洗放电),分别在空气、氩气放电中获得了稳定的单个微放电通道。采用电学及光谱方法,研究了微放电通道中等离子体参量的变化及其空间分布。在空气中,通过“清洗放电”,在气压高于0.25atm时,可以得到单个稳定的丝状放电。而气压低于0.25atm时,放电经历类辉光模式、丝放电模式,但最终只能得到弥散放电。利用对电流积分的方法,计算了不同pd值条件下空气放电中单个微放电通道的输运电量。结果发现,单个微放电通道的输运电量与气压关系不大,但随放电间距的增大而增大。采用光谱方法,研究了单个微放电通道中等离子体参量的空间分布。实验发现,光谱强度在放电通道的两端最强,而中间最弱,分布基本对称。利用在空气单通道放电中得到的氮分子振动光谱,计算了振动温度在放电通道内的分布情况,结果发现振动温度在放电通道的两侧最低而中心最高。利用在氩气单通道放电中得到的光谱,根据696.54nm谱线的stark展宽,计算了电子密度在放电通道内的分布,结果发现,电子密度在放电通道的两端最高,而中间略小。本工作对于介质阻挡放电模型的建立提供了必要的实验数据,另外对于弄清介质阻挡放电的放电发展过程也很有意义。更多还原

【Abstract】 A stable micro-discharge channel is obtained respectively in air discharge and argon discharge, by using a specially designed dielectric barrier discharge (DBD) system with two water electrodes. A cleaning discharge method is used, which is performed by increasing the applied voltage first until the gas is breakdown and then decreasing the applied voltage. The variations and the spatial distributions of the plasma parameters in the channel are studied by using electrical and spectral methods.In air, by’cleaning discharge’ method, the filamentary discharge with a single stable filament can be observed when the gas pressure p is more than 0.25atm, while the discharge undergoes the sequence of glow-like discharge to filamentary discharge and finally to diffuse discharge, when p is lower than 0.25atm.The transported charges of a mono-filamentary for diverse pd valve are calculated by current integral method. Results show that the transported charge has little relationship with the gas pressure, while increases with the width of the gas gap.The spatial distribution of the plasma parameters in a single micro-discharge channel is investigated by spectral methods. It is found that the intensity of the spectrum is strongest at the two ends of the channel, while weakest in the middle, distributing symmetrically. The spatial distribution of the vibrational temperature is calculated by using the N2 spectrum in the air discharge channel. It is found that the vibrational temperature is lowest at the two end of the channel, while highest in the middle. In addition, the spatial distribution of the electronic density in the discharge channel is also investigated by the Stark broadening of 696.54nm in argon spectrum. Results show that the electronic density is highest at the ends of the discharge channel, while slightly lower in the middle.This work provides necessary data for establishing the model of the dielectric barrier discharge system, and is of great importance to understand the discharge process of DBD.更多还原