暂态强热流作用下钨烧蚀过程的分子动力学模拟
Molecular Dynamics Simulation of Tungsten Ablation under Transient Heat Flux

摘要 采用分子动力学方法, 对金属钨在由离子辐照引起的暂态热流下的烧蚀现象进行研究。建立一维热传模型, 通过施加不同能量的热脉冲, 研究钨靶材的热响应。计算烧蚀阈值并与理论值进行比较, 统计分析烧蚀深度与热脉冲能量的关系。研究热脉冲作用过程中能量的转移分配状况, 并对低于和高于烧蚀阈值下的不同能量分布状况进行讨论。从模拟的角度, 建立一个对钨在离子辐照下烧蚀过程的初步的物理图像。
Abstract The authors adopt molecular dynamics simulations to get a basic physical image of the tungsten ablation phenomenon induced by intense pulsed ions irradiation. A one-dimension heat transfer model is set up and a series of simulations with different pulse energy fluences are applied. Ablation threshold and ablation depth are calculated and compared with thermal dynamic theoretical values. Energy allocation condition of the simulation system are discussed, which depends on whether the pulse energy exceed ablation threshold. Based on the calculation results, the authors drew a preliminary profile of tungsten ablation under a transient high heat flux brought by energetic ions.