大气压微波放电CO_(2)等离子体温度的发射光谱诊断  

Temperature Measurement of Atmospheric-Pressure CO_(2) Microwave Discharge With Optical Emission Spectroscopy

作　　者：李容毅 朱海龙[1] LI Rong-yi;ZHU Hai-long(College of Physics and Electronic Engineering,Shanxi University,Taiyuan 030006,China)

机构地区：[1]山西大学物理电子工程学院,山西太原030006

出　　处：《光谱学与光谱分析》2024年第3期688-692,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(11875039)资助。

摘　　要：大气压微波等离子体因具有活性粒子密度高、气体温度高、能量转换效率高、可控性好等独特优势,在分解和转化二氧化碳治理环境领域展现出重要的应用价值。以大气压微波等离子体的二氧化碳分解与转化为应用背景,开展了大气压微波等离子体的放电特性与温度参数的测量和诊断研究。通过研究等离子体炬的放电形态的变化规律,分析了大气压二氧化碳等离子体的放电特点;利用发射光谱的诊断方法,分析了二氧化碳放电区内产生的C_(2)分子的转动温度,得到了二氧化碳等离子体内不同位置在不同功率和不同气体流量下的放电形态以及温度的变化规律。研究结果表明,这种大气压微波等离子体的放电形态呈现明亮的中心放电区和外围的余辉区,且这两个区域存在清晰的边界;放电区的长度随微波功率增加接近线性增长,受送气流量大小的影响微弱。等离子体发射光谱诊断结果显示,大气压微波等离子体放电过程中,主放电区中除了化学荧光连续谱外还存在很强的C_(2)分子的Swan谱带;基于这一谱带计算得到的主放电区等离子体温度约为6 000 K,且这一温度几乎不随功率和气流的变化;不同中心放电区位置,温度略有变化(±100 K)。Atmospheric pressure microwave plasmas have presented significant application values in decomposing and converting carbon dioxide to treat the environment due to their unique advantages such as high density of active particles,high gas temperature,high energy conversion efficiency,and good controllability.In the work,the discharge characteristics and the temperature parameters of CO_(2) microwave plasma were studied and diagnosed to apply decomposition and conversion of carbon dioxide with atmospheric pressure microwave plasma in the future.The discharge characteristics were investigated by observing the discharge patterns of the plasma,and the rotational temperature of the C_(2) molecule in the exciting region of CO_(2) discharge was diagnosed by means of optical emission spectroscopy;thereby,its variations with respect to different positions,microwave power and gas flow rates were obtained.The results indicate that the discharge patterns of the atmospheric pressure microwave plasma exhibit a bright central discharge region and afterglow region surrounding the central discharge region,and a clear boundary between these two regions can be observed.The length of the central discharge region increases linearly with the increase of microwave power and is weakly affected by an increase inthe gas flow rate.The diagnostic results of optical emission spectroscopy show that during the discharge process,in addition to the continuous chemical fluorescence spectrum,strong Swan bands of C_(2) molecules exist in the central discharge region.The plasma temperature in the central discharge region calculated based on the optical emission spectroscopy is approximately 6000 K,and it almost no changes with varieties of power and gas flow rate and varies slightly(±100 K)at different locations of the central discharge region.

关 键 词：大气压微波放电 等离子体 转动温度 二氧化碳 

分 类 号：O443.1[理学—电磁学]