在基于多元混合物工质气液相平衡计算的基础上，介绍了利用立方型状态方程计算多元混合物节流制冷工质的压力，比热容、温度、焓和熵等平衡物性的方法。根据该方法，计算了一种经过优化的典型混合物的热力性质，并绘制了该混合物制冷工质的温熵（ Ｔ－ Ｓ） 图，图中包含等压线、等焓线以及相分离线。该温熵图比较直观地反映了混合物的基础物性特征， 使对混合物制冷工质的热力循环分析更加方便直观。 Based on the calculation of gas-liquid equilibrium of multiple working fluid, the method for calculating the equilibrium properties of pressure-controlled refrigerant, specific heat capacity, temperature, enthalpy and entropy using cubic equation of state is introduced. According to this method, the thermodynamic properties of an optimized typical mixture are calculated and the thermosensor (T-S) plot of the working fluid for the mixture is plotted, including isobars, isentropic curves, and phase separation lines. The thermogram more intuitively reflects the basic physical characteristics of the mixture, so that the refrigerant mixture of the thermodynamic cycle analysis more convenient and intuitive.