少量氧气对大气压氩氧混合气体放电特性的影响

Effect of small admixtures of oxygen on the characteristics of argon and oxygen mixture discharge at atmospheric pressure

基于一维流体模型,采用数值模拟的方法研究了大气压氩氧混合气体放电中少量氧气含量对放电特性的影响。根据模型方程进行了数值模拟分析,计算结果表明:随着氧气含量由0.1%增加到0.6%,电子密度减小,O-离子密度增加,总的负粒子密度增加,鞘层区电子温度增加。随着放电时间的增加,O-离子密度增加,电子密度的变化分为三个阶段:电子密度快速增长阶段、电子密度下降阶段和电子密度稳定阶段。当氧气含量小于1%时,电子密度随着氧气含量的增加迅速减小,氧原子密度快速增加;氧气含量大于1%小于4%时,电子密度随氧气含量的增加而缓慢减少,氧原子密度缓慢增加直至不变。

Based on 1-D fluid Model, numerical simulation was adopted to study the effect of small admixtures of oxygen on the characteristics of argon and oxygen mixture discharge at atmospheric pressure. According to the model equations, the simulation results showed that as the ratio of oxygen to argon increased from 0.1% to 0.6%, the electron density decreased, the density of O- increased, the density of the total negative particles increased, the electron temperature in sheath decreased. Furthermore, with the increase of discharge time, the density of O- increased, the electron density was obviously divided into three stages： the stage of electron growth, the stage of electron reduction and the stage of electron unchanged. When the ratio of oxygen to argon was within the scope of 1%, the electron density decreased rapidly, the oxygen atom density increased quickly. However, when the ratio of oxygen to argon was between 1% and 4%, as the ration of oxygen to argon increased the electron density decreased slowly and the oxygen atom density grew slowly until held the line.