氘的气液界面及相变特性分子动力学仿真  

Molecular Dynamics Simulation of Gas-liquid-solid Interface and Phase Transition Characteristics of Deuterium

作　　者：周绍华[1] 黄永华[1,2,3] ZHOU Shaohua;HUANG Yonghua(Institute of Refrigeration and Cryogenics ,Shanghai Jiao Tong University Shanghai 200240, China;Shanghai Cryogenic Technology and Service Center Shanghai 200240, China;Joint Laboratory of cryogenic power technology for aerospace systems, Shanghai 200240, China)

机构地区：[1]上海交通大学制冷与低温工程研究所,上海200240 [2]上海市低温技术与测试应用服务平台,上海200240 [3]宇航系统低温动力技术联合实验室,上海200240

出　　处：《低温物理学报》2018年第1期49-55,共7页Low Temperature Physical Letters

基　　金：上海航天技术研究院-上海交大航天先进技术联合研究中心资助项目(USCAST2016-32);国家自然科学基金(51676118);上海市研发平台专项(16DZ2291500)资助的课题~~

摘　　要：氘作为重要的核聚变原料,其热物性数据是基础,而气液相界面特性和相变规律又是热物性的关键.国内外对氘的相界面特性研究甚少.本文基于分子动力学方法,采用截断移位Lennard-Jones 12-6势能函数模型描述原子间的相互作用,并考虑分子内部原子间键的谐振作用,对氘的气液界面特性及气液固相变过程进行了仿真研究,得到了氘在不同温度下气液界面过渡区域的厚度、表面张力值等;获得了氘的密度随相变过程的变化规律,并由此得出氘的熔沸点温度,上述计算结果与实验及文献值吻合良好.不仅从微观层面上揭示了氘的宏观热物性表征机理,而且所建立的仿真模型可直接用于预测缺乏实验工况下的氘热物性.As an important nuclear fusion material,the thermal physical data of deuterium are the basis for its study.The characteristics of the gas-liquid interface and phase transition are the key to the thermophysical properties.However,there are few studies on the properties of the deuterium interface at home and abroad.Gasliquid interface characteristics and process of gas-liquid-solid phase transformation are simulated based on molecular dynamics method using the truncated shift Lennard-Jones 12-6 potential energy function model to describe the interaction between atoms,considering the resonance of interatomic bonds.The gas-liquid interface thickness and surface tension value are obtained.We also get the melting point and boiling point of deuterium by analysis of phase transition process.The simulation results in this paper are in good agreement with the experimental data and literature values.This paper not only reveals the macroscopic thermal physical properties of deuterium from the microscopic level,but also can be used to predict deuterium thermal properties under the lack of experimental conditions.

关 键 词：氘 气液界面 相变 分子动力学 表面张力 熔点 沸点 

分 类 号：O561[理学—原子与分子物理]