圆筒内氢等离子体非定常化学反应羽流场DSMC分析

利用直接模拟Monte Carlo方法研究圆筒侧壁注入氢等离子体羽流场在8×10^-6s内的非定常流动特性.根据Bird的化学反应模型考虑离解-复合反应模型和电荷转移反应模型.在流场中注入H₂、H、金属原子X、H₂⁺和H⁺五种组分，研究离解-复合反应对流场中粒子分布和密度的影响，结果表明离解-复合反应使H₂数密度降低，H数密度增加，说明在流场中H₂的离解反应速率大于H的复合反应速率.加入电荷转移反应后H₂⁺数密度降低，H⁺数密度增加，对其他组分数密度没有显著影响.

DSMC Analysis of Unsteady Chemical Reactions of Hydrogen Plasma in Cylinder

Unsteady flow characteristics of particles in plumes are studied with direct simulation Monte-Carlo method (DSMC) in an 8×10^-6 s period. Dissociation model, recombination model and charge exchange model are included based on Bird's chemical reaction models. Molecular hydrogen H₂, atomic hydrogen H, atomic metal X, ion H₂⁺ and ion H⁺ are included. Influence on density distribution of particles in the field due to dissociation and recombination is studied. It shows that the number density of molecular hydrogen H₂ decreases and the number density of atomic H increases since dissociation rate of molecular hydrogen H₂ is faster than recombination of atomic H in the flow field. A charge exchange model is added in dissociation and recombination models. It shows that the number density of ion H₂⁺ decreases and the number density of ion H⁺ increases obviously in charge exchange model.