A generalized isobaric specific heat capacity model for hydrocarbons, hydrofluorocarbons, hydrofluoroolefins and their mixtures in the liquid phase

Hydrocarbons (HCs), hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs) and their mixtures are important industrial fluids, widely used in energy, refrigeration and other fields. Their high-precision isobaric specific heat capacity (c(p)) data is essential for process optimization and heat exchanger design. However, no high-precision generalized c(p) equation has been publicly reported for liquid HCs, HFCs, HFOs and their mixtures. In this paper, by deeply analyzing the variation rule between the experimental c(p) data and the calculated value of Peng-Robinson equation of state (PR EoS), a new generalized model is established for liquid HCs, HFCs, HFOs and their mixtures at wide temperature and pressure range (0.215 <T-r < 0.998; 0.020 <p(r) <94.595). The average absolute relative deviation (AARD) of 4069 data points of 34 pure substances is 1.70 %. Combined with the generalized mixing rules, the new model achieves a good prediction for liquid c(p) of mixtures, and the AARD of 1051 data points of 17 mixtures is 1.55 %.