关于弯曲界面气液两相相平衡化学势相等热力学判据的讨论

Discussion on Thermodynamic Criterion of Equal Chemical Potential for Phase Equilibrium between Gas and Liquid in Curved Interface

弯曲界面气液两相相平衡时化学势相等的热力学判据见诸于大量教材和论文。本文对现有教材中关于该判据的推导过程进行了分析,认为该判据的证明过程存在问题。为解决该问题,本文从化学势的定义出发提供了一种化学势相等热力学判据的新证明过程。同时,本文还依据吉布斯界面热力学理论建立了另一种弯曲界面气液两相相平衡的热力学新判据,并以此为基础进行开尔文公式的推导。新判据直接从热力学第二定律出发,热力学意义明确,物理模型清晰,整个推导过程简洁明了。

Thermodynamic criterion of equal chemical potential for phase equilibrium between gas and liquid in curved interface has been introduced in many textbooks and papers. In this paper, the process of the derivation of the criterion is proved to be wrong with analysis. In order to solve the problem, a proof procedure for the thermodynamic criterion of equal chemical potential is provided based on the definition of chemical potential. At the same time, a new thermodynamic criterion of two-phase equilibrium in curved interface is established using Gibbs interface thermodynamics and a new method for derivation of Kelvin equation is put forward based on the thermodynamic criterion of two-phase equilibrium. The new criterion which is derived directly from the second law of thermodynamics has a specific thermodynamic significance and clear physical model.