最小能量函数法求解多元相平衡

根据孤立系统平衡时熵最大原理,利用已有的优化工具包,在一定温度和压力下,使系统吉布斯自由能最小化,求解多元相平衡问题.作为实例,给出了绿色制冷剂R32与R134a混合体系在不同压力(20 kPa～5MPa)下平衡组分的计算结果;该结果同已有的实验数据吻合.由于该方法的基础性和一般性,有望成为包括流体流动、浓度扩散、物质相变以及化学反应在内的复杂过程的统一的热力学处理方法.

Phase equilibrium calculation by minimization of energy function

Based on the principle of the maximum entropy at system equilibrium, equilibrium of a multicomponent multiphase system is determined by minimizing the Gibbs free energy at a given temperature and pressure with available optimum toolbox. As an example, equilibrium compositions of a binary mixture of green refrigerating media, R32 and R134a, are predicated in a wide range of pressure (20 kPa~5 MPa), which agree with the measured data. Because of its groundwork and generality, the proposed method is promising to become a uniform thermodynamic method for complex processes accompanying with fluid flow, concentration diffusion, phase change and chemical reaction.