直流驱动氩气等离子体刷的放电特性研究  

Discharge characteristics of a brush-shaped argon plasma plume driven by a direct-current voltage

作　　者：李雪辰[1,2] 李霁媛 张春艳[1] 

机构地区：[1]河北大学物理科学与技术学院,保定071002 [2]河北省光电信息材料重点实验室,保定071002

出　　处：《中国科学：物理学、力学、天文学》2015年第9期50-57,共8页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(批准号:10805013;51077035);河北省杰出青年基金(编号:A2012201045);河北省自然科学基金(编号:A2011201134);河北省教育厅优秀青年项目(编号:Y2011120);中西部高校综合实力提升工程资助项目

摘　　要：采用线-板放电装置,通过氩气的流动,在直流电压驱动下产生了大面积的大气压均匀刷形等离子体羽,并利用光学方法对其放电特性进行了研究.结果表明,虽然外加电压是直流形式,但放电电流和放电发光是周期性的脉冲信号.利用光电倍增管测量了光脉冲的频率,发现放电频率随着电压或气流的增加而增大.对等离子体羽的发光信号沿着线电极方向和沿着气流方向分别进行了空间分辨测量,发现刷型等离子体羽由微放电构成.微放电沿着线电极方向在时间上是随机出现的,而沿着气流方向以"等离子体子弹"传播.利用光谱仪测量了放电的发射光谱,并且通过发射光谱计算了分子振动温度.研究发现,分子振动温度随着电压增加而增加,随着气流的增加而减小.A stable plasma plume in brush shape is generated with fairly large area in the ambient air at atmospheric pressure through using argon as the working gas and a direct-current （DC） excited line-plate discharge device. The discharge characteristics of the brush-shaped plume are investigated by optical method. Results show that both the light emission and the current signal are periodically pulsed despite that the discharge is excited by the DC power supply. The light emission frequency is investigated through a photomultiplier tube, and it is found that the discharge frequency increases with increasing the applied voltage or the gas flow rate. Spatially resolved measurements are conducted for the light emission from the plasma plume along the ground electrode and the gas flow, respectively. Results indicate that the uniform plume is composed of micro-discharges, which appear stochastically in time along the line electrode. Along the gas flow direction, the microdischarge propagates in the method of plasma bullets in a high velocity. The optical emission spectrum from the plume is detected by a spectrometer, and the molecular vibrational temperature is calculated based on the discharge spectrum. It is found that the molecular vibrational temperature increases with increasing the voltage or decreasing the gas flow rate.

关 键 词：等离子体羽 大气压均匀放电 空间分辨测量 等离子体子弹 放电频率 

分 类 号：O53[理学—等离子体物理]