大气压氦气介质阻挡放电的二维演化过程  

Axial and Radial Evolution of the Dielectric Barrier Discharge in Helium at Atmospheric Pressure

作　　者：梁卓[1] 罗海云[2] 王新新[2] 吕博[2] 关志成[1] 王黎明[1] 

机构地区：[1]清华大学深圳研究生院,深圳518055 [2]清华大学电机系,北京100084

出　　处：《高电压技术》2008年第2期377-381,共5页High Voltage Engineering

基　　金：国家自然科学基金(50537020);博士点专项基金(20040003011)~~

摘　　要：为了研究大气压氦气的介质阻挡放电机理,利用像增强高速相机(ICCD),以20ns曝光时间,拍摄了多组时序发展的时空分辨放电图像,揭示了放电形式由汤森放电向辉光放电的演化。所测阴极位降区厚度0.4mm,应属亚辉光放电类型,而底面拍摄的图像则揭示了放电径向发展的过程。将放电图像转化为可视性更强的三维图像后,发现放电由覆盖整个电极的微弱汤森放电起始,在场强略高的中心处率先发展,并迅速向外扩散。Dielectric barrier discharge in helium at atmospheric pressure was studied by taking fast images of the discharge during one current pulse using a fast-gated intensified charge coupled device（ICCD）camera. It was observed that there appeared a weak luminous layer close to the anode at the very beginning of the discharge, and then the luminous area gradually expanded into the entire gap as the anode layer moves towards to the cathode, finally a strong luminous layer formed close to the cathode at the time around the maximum of the current pulse. The evolution of the discharge pattern indicates a transition from Townsend discharge to glow discharge. The measured thickness of cathode fall is 0.4mm, which indicates the discharge being a subnormal glow discharge. The radial evolution of dielectric barrier discharge in helium at atmospheric pressure was also studied by taking end-view photographs of the discharge during one current pulse using the ICCD. The photographs were transformed into three-dimensional ima- ges that make the radial evolution of the discharge more visualized. It was found that the discharge began with a weak Townsend discharge covering the entire electrode surface, developed much more rapidly in the central part where the electric field is higher, and spread rapidly outwards.

关 键 词：介质阻挡放电 高速摄影 汤森放电 辉光放电 图像处理 透明电极 

分 类 号：O461.2[理学—电子物理学]