In this work, it was found that the experimental heat capacity difference (c_p-c_v)_exp has a linear relationship with the heat capacity difference calculated by using PR equation (c_p-c_v)_PR. Based on this linear relationship, a predicted model of isobaric heat capacity for liquid refrigerants was presented. The accurate isobaric heat capacity of refrigerants in liquid phase can be obtained if the critical temperature, critical pressure, critical density, acentric factor and several experimental isobaric heat capacity data (at least two, more is better) are known. The proposed model was applied to 17 refrigerants (including HC, HFC, HFO and HCFO refrigerants) and a comparison was performed between the calculations by the proposed model and the experimental heat capacity data to validate the prediction. The results indicated the proposed method can represent the isobaric heat capacity of 17 refrigerants in liquid state with an average absolute deviation of 1.00%. The performance of this proposed method was then compared with that of other models (including Helmholtz equation, Peng-Robinson equation and a generalized corresponding state principle equation). It can be concluded that the proposed method generally shows better performance than other models. In addition, the proposed model reveals a good extrapolation ability in low temperature regions for refrigerants.

在这项工作中，发现实验热容差（c _p - c _v）_exp与使用PR方程（c _p - c _v）_PR计算的热容差具有线性关系。。基于该线性关系，提出了液态制冷剂的等压热容预测模型。如果已知临界温度，临界压力，临界密度，偏心因数和几个实验性等压热容量数据（至少两个，更好的话），则可获得制冷剂在液相中的精确等压热容量。将该模型应用于17种制冷剂（包括HC，HFC，HFO和HCFO制冷剂），并对该模型的计算结果与实验热容量数据进行了比较，以验证预测结果。结果表明，该方法可以代表17种液态制冷剂的等压热容，平均绝对偏差为1.00％。然后将该方法的性能与其他模型（包括Helmholtz方程，Peng-Robinson方程和广义对应状态原理方程）的性能进行了比较。可以得出结论，所提出的方法通常表现出比其他模型更好的性能。此外，所提出的模型还显示了在低温区域对制冷剂具有良好的外推能力。