Atmospheric microwave-induced plasmas in Ar/H2 mixtures studied with a combination of passive and active spectroscopic methods
Atmospheric microwave-induced plasmas in Ar/H2 mixtures studied with a combination of passive and active spectroscopic methods
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DOI：
10.1088/0022-3727/43/39/395202
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发表时间：
2010-10
期刊：
影响因子：
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通讯作者：
J. M. Palomares;E. Iordanova;A. Gamero;A. Sola;J. Mullen
中科院分区：
文献类型：
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作者：
J. M. Palomares;E. Iordanova;A. Gamero;A. Sola;J. Mullen
几种主动式和被动式诊断方法已被用于研究由工作频率为2.45 GHz、功率值在57至88 W之间的表面加速器产生的大气微波诱导等离子体。通过对结果的比较，深入了解了必要的等离子体量、它们的径向分布以及诊断方法的可靠性。使用了两种激光技术，即用于测定电子密度ne和温度Te的汤姆逊散射和用于测定重粒子温度Tg的瑞利散射。结合三种无源光谱技术，利用Hβ谱线增宽法测定ne，用两种绝对强度测量法测定ne和Te。主动技术提供了尺寸在0.5 mm左右的小等离子体的空间分辨率。用三种不同的方法测量的结果显示出良好的一致性，与等离子体设置无关。在纯氩等离子体条件下，两种方法得到的Te值基本一致，但在引入H2时，结果出现偏差。在氩等离子体中加入少量（0.3%）的H2会引起收缩，减少ne，增加Te，增强偏离平衡的程度，并导致接近低温大气等离子体的条件。
Several active and passive diagnostic methods have been used to study atmospheric microwave-induced plasmas created by a surfatron operating at a frequency of 2.45 GHz and with power values between 57 and 88 W. By comparing the results with each other, insight is obtained into essential plasma quantities, their radial distributions and the reliability of the diagnostic methods. Two laser techniques have been used, namely Thomson scattering for the determination of the electron density, ne, and temperature, Te, and Rayleigh scattering for the determination of the heavy particle temperature, Tg. In combination, three passive spectroscopic techniques are applied, the line broadening of the Hβ line to determine ne, and two methods of absolute intensity measurements to obtain ne and Te. The active techniques provide spatial resolution in small plasmas with sizes in the order of 0.5 mm. The results of ne measured with three different methods show good agreement, independent of the plasma settings. The Te values obtained with two techniques are in good agreement for the condition of a pure argon plasma, but they show deviations when H2 is introduced. The introduction of a small amount (0.3%) of H2 into an argon plasma induces contraction, reduces ne, increases Te, enhances the departure from equilibrium and leads to conditions that are close to those found in cool atmospheric plasmas.