为了深入理解不同的等离子体发生器几何结构对其放电特性的影响规律,采用一维流体模型对平板型和同轴型两种不同结构等离子体发生器的放电特性进行了数值模拟研究,并对放电图像采用可见光图像处理技术进行了分析。数值模拟结果表明,平板型等离子体发生器所产生的等离子体主要参数(如电子温度和活性粒子浓度等)关于两电极中间平面对称,而同轴型等离子体发生器所产生的等离子体主要参数则呈现出非对称的分布规律,这与放电图像灰度值的空间分布规律定性一致。通过对等离子体中化学反应动力学过程的分析可知,不同结构发生器所对应的等离子体主要参数的空间分布规律依赖于不同电极结构所导致的放电区电场强度的空间分布。
In order to investigate the discharge characteristics of the plasma generators with different geometrical configurations, a one-dimensional fluid model was employed to simulate the discharge features of the planar-type and co-axial-type radio-frequency atmospheric-pressure glow discharge {RF APGD) plasma generators. And typical discharge images are analyzed by using the visible image processing technique. The modeling results show that the parameters of the plasmas (e. g. , the distributions of the electron temperature and the species number densities, etc. } produced by the planar-type generator are symmetric about for mid-plane between the electrodes, while the asymmetric features become significant with the co-axial-type generator. The spatial distributions of the plasma parameters using the different types of plasma generators are qualitatively consistent with the corresponding distributions of the grayscale values of the discharge images. The analysis of the chemical reactions shows that the spatial distributions of the plasma parameters are dependent on the electric field distributions resulting from the different electrode configurations of the plasma generators.