常压空气介质阻挡放电的能量传递过程

Energy Transfer Processes in Atmospheric Dielectric Barrier Discharge in Air

利用发射光谱技术分析空气等离子体中可能存在的化学活性物质,并通过分析空气等离子体中氮气、氧气常见激发态的产生和猝灭过程,结合其动力学数据,计算分析了常压空气介质阻挡放电中的能量传递过程。结果表明,氮分子和原子的激发态很快通过与分子、原子间的碰撞而猝灭掉或被氧分子、原子氧化而生成氮氧化合物,氧分子的激发态由于其本身的跃迁几率太小,所以没有测到氧气的发射光谱;放电系统中的电子能量很少有>17.0 eV的,但存在能量>11.03 eV的电子,与计算得到的电子能量分布一致;约化场强E/N>150 Td时,电子与氮分子激发、离解碰撞的能量损失占电子碰撞能量损失的50%以上;氮分子、原子激发态的存在可以提高O、O3以及一些氮氧化合物的粒子数浓度。

The chemical active species which might existed in air plasma were analyzed with the diagnostic techniques of optical emission spectroscopy.The energy transfer processes in atmospheric DBD in air were analyzed with the thermodynamic data of excitation,dissociation and quenching processes of nitrogen and oxygen in air plasma.The results show that： excited states of nitrogen molecules and atoms are quenched by collisions with other atoms and molecules or oxidized to oxynitride by oxygen molecules or atoms.The emission spectra of oxygen are not detected is their extremely low transition probability.There are few electrons with energy higher than 17.0 eV,but electrons with 11.03 eV exist in the DBD system indeed which are consistent with calculated electron energy distribution.The energy branching of nitrogen excited and dissociated collisions in electron collisions exceeds 0.5 when reduced electric field is higher than 150 Td.The number densities of O,O_3,and some oxynitrides increase when the excited states of nitrogen molecule and atom are considered.