TY - JOUR
T1 - Ideal-Gas Heat Capacities and Virial Coefficients of HFC Refrigerants
AU - Yokozeki, A.
AU - Sato, H.
AU - Watanabe, K.
N1 - Funding Information:
The authors are indebted to the New Energy and Industrial Technology Development Organization, Tokyo, for financial support of the present study. They also thank Dr. R. Tillner-Roth for various constructive comments and discussions and Mr. J. Li for his elaborate contribution in preparing the original drawings.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1998
Y1 - 1998
N2 - Thermodynamic properties of HFC (hydrofluorocarbon) compounds have been extensively studied with worldwide interest as alternative refrigerants. Both quality and quantity in the experimental data far exceed those for the CFC and HCFC refrigerants. These data now provide a great opportunity to examine the validity of theoretical models, and vice versa. Among them, the ideal-gas heat capacity (C0p) and virial coefficients derived from the experimental data are of particular interest, since they are directly related to the intramolecular and intermolecular potentials through the statistical mechanical procedure. There have been some discrepancies reported in the observed and theoretical C0p for HFC compounds. We have performed new calculations of C0p for several HFCs. The present results are consistent with the selected experimental values. The second (B) and third (C) virial coefficients have been reported for these HFC refrigerants from speed of sound data and Burnett PVT data. Often, a square well-type intermolecular potential is employed to correlate the data. However, the model potential cannot account consistently for both B and C coefficients with the same potential parameters. We have analyzed the data with the Stockmayer potential and obtained self-consistent results for various HFC (R-23, R-32, R-125, R-134a, R-143a, and R-152a) compounds with physically reasonable potential parameters.
AB - Thermodynamic properties of HFC (hydrofluorocarbon) compounds have been extensively studied with worldwide interest as alternative refrigerants. Both quality and quantity in the experimental data far exceed those for the CFC and HCFC refrigerants. These data now provide a great opportunity to examine the validity of theoretical models, and vice versa. Among them, the ideal-gas heat capacity (C0p) and virial coefficients derived from the experimental data are of particular interest, since they are directly related to the intramolecular and intermolecular potentials through the statistical mechanical procedure. There have been some discrepancies reported in the observed and theoretical C0p for HFC compounds. We have performed new calculations of C0p for several HFCs. The present results are consistent with the selected experimental values. The second (B) and third (C) virial coefficients have been reported for these HFC refrigerants from speed of sound data and Burnett PVT data. Often, a square well-type intermolecular potential is employed to correlate the data. However, the model potential cannot account consistently for both B and C coefficients with the same potential parameters. We have analyzed the data with the Stockmayer potential and obtained self-consistent results for various HFC (R-23, R-32, R-125, R-134a, R-143a, and R-152a) compounds with physically reasonable potential parameters.
KW - Heat capacity
KW - Hydrofluorocarbons
KW - Ideal gas
KW - Stockmayer potential
KW - Virial coefficient
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U2 - 10.1023/A:1021499018749
DO - 10.1023/A:1021499018749
M3 - Article
AN - SCOPUS:0031702574
SN - 0195-928X
VL - 19
SP - 89
EP - 127
JO - International Journal of Thermophysics
JF - International Journal of Thermophysics
IS - 1
ER -