Molecular simulation for R1123 thermophysical properties

Abstract

Refrigerants used in refrigeration and air-conditioning systems are required to be shifted to those with low global warming potential. In this study, a method to improve the prediction accuracy is proposed for low-temperature properties of R1123 (Trifluoroethene), one of the candidates for the new refrigerant, by clarifying issues in molecular simulations and utilizing quantum chemical simulations and measurement data at temperatures relatively high. The Lennard-Jones parameters to be modified were identified based on the interaction in R1123 dimer, and fine-tuned by referring to the measured saturated liquid density. The adjusted molecular force field was used to obtain satisfactory reproducibility in saturation pressure, surface tension, and second virial coefficient. On the other hand, significant error in the prediction of the vapor dielectric constant and third virial coefficient was found.