摘要
从分子动力学方法出发,对氩蒸气均匀核化过程进行了模拟,并分别采用经典均匀成核理论(CNT)预测、Cluster分析以及平均第一次出现时间(MFPT)3种方法进行了成核率计算.模拟结果表明,在相同条件下,Cluster分析法及MFPT方法得到的成核率在同一个数量级,而CNT预测的成核率比Cluster分析法及MFPT方法得到的成核率小3个数量级,其差异可由推导CNT成核率时对Cluster所做的平衡热力学假定进行解释.3者得到的临界Cluster分子数均为20左右.由Cluster分析方法可知,成核率随冷却脉冲强度增大而增大,这与实际均匀核化过程一致.
The molecular dynamic simulation was performed on the homogenous nucleation of argon vapor, and the nucleation rate was calculated by classic nucleation theory（CNT）, mean firstpassage times（MFPT）, and cluster theory, respectively. The simulation results show that under the same simulation condition, the nucleation rates calculated by the MFPT and the cluster theory are of the same order of magnitude, and are of three orders of magnitude higher than those calculated by the CNT theory because of the equilibrium thermodynamics assumption with the CNT theory. Moreover, the critical cluster number of homogenous nucleation for the three methods is close to 20. In addition, from the cluster theory analysis, the nucleation rate increases with the increase in the cooling rate, which agrees well with practical homogeneous nucleation.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2009年第9期32-36,共5页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(50376077
50776101)
