Plasma chemistry model of surface microdischarge in humid air and dynamics of reactive neutral species
Plasma chemistry model of surface microdischarge in humid air and dynamics of reactive neutral species
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DOI：
10.1088/0022-3727/45/42/425201
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发表时间：
2012-10-24
影响因子：
3.4
通讯作者：
Morfill, Gregor E.
中科院分区：
文献类型：
--
作者：
Sakiyama, Yukinori;Graves, David B.;Morfill, Gregor E.
本文建立了常压下潮湿空气中表面微放电的数值模型。我们的模型包括超过50种物质和600种基本反应，并由两个耦合良好混合的区域组成：带电和中性物质的放电层和仅由中性物质组成的余辉区。在我们的模型中采用了多个时间步长，可以捕获放电层中的快速动态行为以及余辉中相对缓慢的扩散和反应。假设在放电区域以10 kHz的频率激发短时间的高电场，功率密度维持在0.05 W cm（-2）。预计余辉中的优势物质为O-3、N2O5、N2O、HNO3、H-2、NO3、H2O2、HNO2和NO2。结果与傅里叶变换红外吸收光谱定性一致。我们的模拟结果表明，即使在SMD暴露约15分钟后，这些反应性物种的密度也会随着时间的推移而继续显著变化。这一结果表明，在几分钟或更短的时间内，SMD处理可能涉及显著的中性物种浓度和通量瞬变，可能影响结果的解释。
We present a numerical model of a surface microdischarge (SMD) in humid air at atmospheric pressure. Our model includes over 50 species and 600 elementary reactions and consists of two, coupled well-mixed regions: a discharge layer with both charged and neutral species and an afterglow region consisting only of neutral species. Multiple time steps employed in our model enable capturing rapid dynamic behaviour in the discharge layer as well as the relatively slow diffusion and reaction in the afterglow. A short duration, high electric field is assumed to be excited at 10 kHz in the discharge region with power density maintained at 0.05 W cm(-2). Among the predicted dominant species in the afterglow are O-3, N2O5, N2O, HNO3, H-2, NO3, H2O2, HNO2 and NO2. The results are in qualitative agreement with Fourier transform infrared absorption spectroscopy. Our simulation results show that density of those reactive species continues to evolve significantly in time, even after similar to 15 min of SMD exposure. This result suggests that SMD treatments on the order of minutes or less may involve significant neutral species concentration and flux transients, potentially affecting interpretation of results.