大气压下氦气、甲烷、空气等离子体射流发射光谱诊断研究  

Diagnosis of Emission Spectroscopy of Helium,Methane and Air Plasma Jets at Atmospheric Pressure

作　　者：田富超 陈雷 裴欢 白洁琪 曾文 TIAN Fu-chao;CHEN Lei;PEI Huan;BAI Jie-qi;ZENG Wen(State Key Laboratory of Coal Mine Safety Technology,China Coal Technology&Engineering Group Shenyang Research Institute,Shenfu Demonstration Zone,Shenyang 113122,China;School of Aero-Engine,Shenyang Aerospace University,Shenyang 110136,China)

机构地区：[1]中煤科工集团沈阳研究院有限公司煤矿安全技术国家重点实验室,沈抚示范区,辽宁沈阳113122 [2]沈阳航空航天大学航空发动机学院,辽宁沈阳110136

出　　处：《光谱学与光谱分析》2023年第9期2694-2698,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(52174229,52174230),辽宁省自然科学基金项目(2020-KF-13-03)资助。

摘　　要：在等离子体射流的辅助下,液体的雾化特性能够得到一定程度的改善,等离子体辅助雾化具备应用于超细水雾抑制瓦斯爆炸领域的潜力。然而,由于等离子体射流中存在的多种活性粒子对于燃烧存在促进作用,因此有必要对瓦斯气体存在的条件下等离子体中的活性粒子种类进行定量分析。在大气压下开展了以氦气作为载气对预混的甲烷和空气进行介质阻挡(DBD)放电研究。结果表明,等离子体射流中的主要活性粒子为OH基团、N_(2)的第二正带系、CH基团、HeI原子以及少量的O原子,其中甲烷电离区的谱线主要集中在400~600 nm。增大峰值电压和氦气掺混体积流量比都可以有效提高等射流中活性基团的含量。采用N_(2)第二正带系的连续谱带做最小二乘线性拟合,对等离子体射流的振动温度进行了计算,得到大气压氦气/空气-甲烷等离子体射流的振动温度在2000~4000 K之间。随着峰值电压和氦气掺混比的增大,振动温度都呈现增大趋势。利用HeI原子激发能差较大的5条谱线做最小二乘线性拟合,对等离子体射流的电子激发温度进行了计算,得到大气压氦气/空气-甲烷等离子体射流的电子激发温度在3500~13000 K之间。随峰值电压的增大,电子激发温度表现出增大的变化趋势,随着氦气掺混比的增大,电子激发温度表现出减小的变化趋势,分析发现随着氦气体积流量的增大,使得射流发生器内的气流变快,带走了发生器内更多的热量,导致电子激发温度下降。With the plasma jet's aid,the liquid's atomization characteristics can be improved to a certain extent.It can be seen that plasma-assisted atomization has the potential to be applied in the field of ultra-fine water mist to suppress gas explosions.However,since various active particles in the plasma jet have a promoting effect on combustion,it is necessary to quantitatively analyze the active particle species in the plasma in the presence of gas.In this study,a DBD discharge study was performed on premixed methane and air under atmospheric pressure using helium as the carrier gas.The needle-ring dielectric barrier plasma generator ionizes the helium/methane-air mixture at a discharge frequency of 10 kHz and atmospheric pressure and generates a stable plasma jet.Diagnosis of the active particle types,vibration temperature and electron excitation temperature of the plasma jet under the conditions of different peak voltages and different mixing volume flow ratios by emission spectroscopy.The results show that the main active particles in the plasma jet are the OH group,the second positive band of N_(2),the CH group,HeⅠ,and a small number of O atoms.Among them,the methane ionization region is mainly concentrated in the 400 to 600 nm range between.Increasing the peak voltage and the helium mixing volume flow ratio can effectively increase the content of active groups in the isojet.Using the continuous band of the second positive band of N_(2) to do the least square linear fitting,the vibration temperature of the plasma jet is calculated,and the vibration temperature of the atmospheric pressure helium/air-methane plasma jet is between 2000 and 4000 K.The vibration temperature shows an increasing trend with the increase of peak voltage and helium mixing ratio.Using five spectral lines with a large difference in excitation energy of HeⅠatoms to do the least squares linear fitting,the electron excitation temperature of the plasma jet is calculated,and the electron excitation temperature of the atmospheric pressure hel

关 键 词：介质阻挡放电 发射光谱 电子激发温度 振动温度 

分 类 号：O433.1[机械工程—光学工程]