Molecular dynamics simulation of water vapor nucleation induced by ions

doi:10.7523/j.issn.2095-6134.2016.02.013

Abstract

Abstract:

Ion has an important effect on the water vapor nucleation. In this study, molecular dynamics method was employed to investigate the homogenous and ion-induced nucleation processes of supersaturated steam. Effects of charge magnitude on the nucleation process were analyzed based on the results of the molecular dynamics simulation. It has been observed that the process in each case consists of three stages: induction stage, stable nucleation stage, and coagulation stage. The presence of ions leads to shorter induction stage, increase of nucleation rate, and decrease of critical nucleus size, which means that the nucleation process is easier to occur. Moreover, positive divalent ions have greater influence on water vapor nucleation than positive monovalent ions. Finally, the phenomenon is explained using the cluster's micro structure.

Key words: cluster, ions, nucleation, molecular dynamics

CLC Number:

TK123

ZHANG Chao, WANG Yueshe, LI Chenpei. Molecular dynamics simulation of water vapor nucleation induced by ions[J]. , 2016, 33(2): 228-233.

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