The calculation models of vapor-liquid equilibrium, enthalpy and entropy for R152a/R1234ze(E)

Abstract

To mitigate the impact of human activities on the environment, R22 with ODP not equal to 0 and high GWP must be weeded out. R1234ze has excellent environmental performance but insufficient refrigeration capacity per unit. R152a has excellent refrigeration performance but flammability. Their mixture will make up for each other’s defects and can be used as a new alternative refrigerant. Thermodynamic properties of the mixture are studied in this paper. The vapor–liquid equilibrium model, based on Peng–Robinson equation of state and VDWS mixing law, is established for R152a/R1234ze with temperature from 258.15 to 288.15 K. When the results are compared to the values of experiments, the maximal and average errors for pressures are 0.617% and 0.135%, respectively. Based on vapor–liquid equilibrium model combining residual property, enthalpy and entropy models are also established to calculate enthalpy and entropy of mixture (R152a and R1234ze with the mass ratio 60:40), which enable provide theoretical basis for the application of R152a/R1234ze.