建立了一个分子动力学研究蒸汽异质核化的模型,对氩蒸汽异质核化进行MD模拟研究。氩蒸气的初始温度为300 K,冷却终温为80 K,冷却速率为0.0002 m/s。异质核化成核现象表明核化均以固体颗粒为核化中心,核化温度高于均质核化。同时统计了不同氩蒸汽粒子数异质核化的核化团簇的密度、法向压力、切向压力分布,计算团簇的表面张力。异质核化与均质核化的对比表明,均质核化核化中心随机,异质核化以固体颗粒为核化中心;均质核化团簇液相密度分布均匀,异质核化中心固体颗粒处密度高于液相均匀密度,固体颗粒处的液体粒子呈现类固体结构。
In this paper,molecular dynamics simulation method was adopted to establish a new model for vapor heterogeneous nucleation,and it was carried out to simulate heterogeneous nucleation of Argon.The initial temperature of the system is 300 K,then cooling the system to 80 K under the cooling rate 0.0002 m/s.The results show,in heterogeneous nucleation,the nuclei center is the solid particle and nucleation temperature is higher than that of homogenous nucleation.At the same time, the density distribution,as well as the pressure distribution and the surface tension are analyzed for the nucleation cluster.Comparing the heterogeneous nucleation with homogenous nucleation,it shows that a nucleus center of homogenous nucleation is random,while heterogeneous nucleation is centered by the solid particle.The density distribution in bulk liquid is uniform during the process of homogenous nucleation;however in heterogeneous nucleation,there has solid-like structure near the solid surface.