假定烧蚀粒子与环境气体原子均为刚性硬球,采用蒙特卡罗(Monte Carlo)方法,对单脉冲激光烧蚀产生的硅(Si)粒子在1000Pa环境氦(He)气中的传输过程进行了数值模拟,研究了衬底对环境密度恢复时间的影响。结果发现,衬底对粒子完全反弹和完全吸附的情况下对应的环境密度恢复时间分别为1713.2μs和1663.2μs,并且随着衬底对粒子临界吸附速度的增大,环境密度恢复时间先增大后减小。 Assuming that both the ablated particles and the ambient gas atoms are rigid hard balls, the transport of silicon particles generated by single-pulse laser ablation in 1000 Pa ambient helium (He) gas was carried out using the Monte Carlo method Numerical simulation was carried out to study the influence of substrate on the recovery time of environmental density. The results show that the recovery time of ambient density corresponding to the complete rebound and complete adsorption of particles on the substrate is 1713.2μs and 1663.2μs respectively, and the recovery time of the environmental density first increases with the increase of the critical adsorption rate of the particles to the substrate After the decrease.