直接模拟蒙特卡罗法模拟二维平面蒸发亚稳态原子退激过程

Direct-simulation Monte-Carlo Method for Metastable States' Deexcitation in 2-D Evaporation Process

在原子法激光同位素分离 (AVLIS)工程中 ,金属受电子束的加热而熔化 ,有一部分原子处于亚稳态能级 ,为了分析在蒸发过程中亚稳态原子退激对原子蒸气的速度、温度等物理特性的影响 ,采用直接模拟蒙特卡罗 (DSMC)法模拟钆原子蒸发过程 ,分析亚稳态原子退激过程对蒸气特性的影响。模拟结果表明 :亚稳态原子退激使得原子蒸气的速度增加 ,温度升高 ;克努森数Kn越小 ,原子间碰撞越频繁 。

In atomic vapor laser isotope separation, the metal is heated and melted by electron beam, and some atoms are on the metastable states. In order to analyse the influence of metastable states' deexcitation on vapor physical parameters, such as velocity, temperature, direct simulation Monte Carlo method is used to simulate the 2 D gadolinium evaporation from long and narrow crucible. The simulation results show that the metastable states' deexcitation increases the velocity and temperature of the vapor, and the smaller Kn is, the more frequently atoms collide, the larger influence of metastable states' deexcitation is.