DBD等离子体中OH自由基数值模拟研究

Numerical simulation of OH radical in dielectric barrier discharge plasma

在介质阻挡放电H2O/He体系中通过解Boltzmann方程,得到电子能量分布函数,利用得到的电子能量分布函数计算电子-分子碰撞反应速率常数.建立了应用于介质阻挡放电的空间平均的化学动力学模型,研究了H2O/He体系在介质阻挡放电中,OH(X2Π)、OH(A2∑+)和电子的浓度随时间的演变以及不同气体组分对电子、OH(X2Π)和OH(A2∑+)的产生及其时间演变的影响.结果表明OH(X2Π)、OH(A2∑+)的浓度随H2O、O2含量的增加先增大后减小,其规律与部分实验结果能够较好地符合.讨论并分析了产生上述结果的主要物理化学反应过程和机理.

Electron energy distribution functions for H2O/He dielectric barrier discharge plasma were obtained by numerically solving the Boltzmann equation.The electron-molecule reaction coefficients were calculated using the computed electron energy distribution functions.A space averaged chemical kinetics model in dielectric barrier discharge was reported.The evolution of electron,OH（X2Π）and OH（A2∑＋）produced in the H2O/He dielectric barrier discharge plasma as a function of time was studied.The generation of electron,OH（X2Π）and OH（A2∑＋）as well as their evolution under the influences of various gas components was also discussed.The results show that the concentrations of OH（X2Π）and OH（A2∑＋）increase while H2O or O2are at low concentration.However,the production of OH（X2Π）and OH（A2∑＋）decreases at higher H2O or O2concentration.The calculated result is compared with the experimental data,and they match well with each other.The reaction mechanisms and the main physicochemical processes involved are also discussed.