气液相变过程亚稳态体相内部界面分析

利用热力学理论对亚稳态体相内部活化分子的聚集状态进行讨论,发现在无外界扰动的平衡状态下,体相内部活化分子绝大多数以单体形式存在,并给出了单体与聚集体的浓度关系。在聚集体浓度与聚集体内部分子数之间关系分析的基础上,推导出临界聚集浓度的表达式,从而确定体相处于过热(过冷)极限点时的内部分子能量分布特性,借以从分子聚集的角度来描述气液相变的物理图景。同时,利用体相在过热(过冷)极限点处的宏观性质来逆推体相与微小新相之间的界面张力γ,从而对经典理论的形核率作出修正。

ANALYSIS OF SURFACE INSIDE METASTABLE BULK PHASE DURING GAS-LIQUID PHASE TRANSITION

The thermodynamics theory was used to discuss aggregation of active molecules inside metastable bulk phase. The study proposed that most of active molecules were isolated monomers inside bulk phase and determined the correlation between monomer and aggregate concentrations. Based on the concentration correlation, the study deduced expression of critical aggregation concentration, determined energy distribution of active molecules inside bulk phase at superheat and supercooling limit state, used molecule aggregation theory to describe gas-liquid phase transition process. Finally, the macroscopic properties of bulk phase at superheat and supercooling limit were used to determine the surface tension 7 between bulk phase and microscopic new phase and to correct traditional nucleation rate theory.