摘要
以能量公设为基础,从非平衡热力学的层面推广了化学势的定义,由此得到了有外场作用下汽液相变的动力学模型。在此基础上,分析了外场影响汽液相变的机理。结果表明,外场既可以加快物质的相变速率,也可以减慢物质的相变速率,还可以改变原来相变的变化方向。以水蒸气凝结成水滴的相变过程为例,当以电离子为水滴凝结核时,电离子激发的电场可加快水滴的生长,这与雷雨天空中或威耳孙云室中的水蒸气容易凝结的现象一致。
According to the energy postulate, the general form of the chemical potential is deduced from non-equilibrium thermodynamics. A dynamic mode of gas-liquid phase change in external physical fields is established. The mechanism of phase change between liquid stage and gaseous state is interpreted. The results indicate that external physical fields can affect the rate and direction of phase change. Through an example of vapor changing into water drops, it is concluded that the electric field excited by electric-ion can fasten the process of drop growth when electric-ion transforms into condensation drop nucleus. This is in accord with the phenomenon that vapor is easy to coagulate in thunder storm or in Wilson chamber.
出处
《华北电力大学学报（自然科学版）》
CAS
北大核心
2007年第2期15-19,共5页
Journal of North China Electric Power University：Natural Science Edition
基金
973国家重点基础研究发展规划项目资助(G2000026307)
华南理工大学传热强化与过程节能教育部重点实验室访问学者资金资助项目
广西师范大学博士科学研究启动基金资助项目
广西区新世纪教改工程十一五第二批立项项目重点资助
关键词
能量公设
汽液相变
水滴增长
外场
energy postulate
gas-liquid phase change
water drop increase
external physical fields
