水蒸气核化及单体生长过程的分子动力学研究  

Molecular Dynamics Investigation on Nucleation and Monomeric Growth of Water Vapor

作　　者：冯靖伊 张燕平[1] 高伟[1] FENG Jingyi ZHANG Yanping GAO Wei(School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Chin)

机构地区：[1]华中科技大学能源与动力工程学院,武汉430074

出　　处：《动力工程学报》2017年第11期912-917,共6页Journal of Chinese Society of Power Engineering

基　　金：国家重点基础研究发展计划(973计划)资助项目(2015CB251504)

摘　　要：通过分子技术模拟水蒸气凝结过程,采用非平衡分子动力学(NEMD)方法模拟并分析了凝结相变中核化及单体生长过程.计算相变过程中的凝结速率,并研究了核化和单体生长初期液态水的直径与凝结速率之间的关系,同时分析了模拟压力对凝结速率的影响.结果表明:在相同过冷度下,凝结速率随压力的降低而减慢;在核化及单体生长过程中,相同的压力和温度条件下,凝结相变的传热传质效果随着液体直径的增长而改善.The process of water vapor condensation was simulated by molecular techniques,while the nucleation and monomeric growth of water vapor in phase change period were simulated and analyzed using non-equilibrium molecular dynamics（NEMD）method.A calculation was conducted on the steam condensation rate in the process of phase change,with a study on the effects of droplet size on the condensation rate in the initial period of nucleation and monomeric growth,and with an analysis on the influence of simulation pressure on the condensation performance.Results show that in the case of same degree of supercooling,the condensation rate decreases with the reduction of pressure.During the process of nucleation and monomeric growth,both the heat and mass transfer effectiveness are relatively good at the same pressure and temperature,which increase with the rise of droplet sizes.

关 键 词：水蒸气 分子动力学 凝结速率 液体尺寸 传热传质 

分 类 号：TK124[动力工程及工程热物理—工程热物理]