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A Fundamental Equation for Trifluoromethane (R-23)



S G. Penoncello, Eric Lemmon, R. T. Jacobsen, Z Shan


A formulation for the thermodynamic properties of trifluoromethane R-23) is presented. The equation is valid for single-phase and saturation states from the triple point (1 18.02 K) to 475 K at pressures up to 120 MPa. The formulation includes an equation of state and ancillary functions for the estimation of saturation properties. The experimental data used to determine the equationof state included pressure-density-temperature (p-r-T), isobaric heat capacity (cp-p-T), isochoric heat capacity (cv-r-T), saturation heat capacity (cs), speed of sound (w-p-T), and vapor pressure. Comparisons between experimental data and values computed using the formulation are given to verify the uncertainties in the calculated properties. The formulation presented may be used to compute densities to within +O. I %, heat capacities to within +0.5%, speed of sound to within 0.5%, and saturation values to within 0.2%, except near the critical point.
J. Phys. & Chem. Ref. Data (JPCRD) -
No. 4


equation of state, R-23, thermodynamic properties, trifluoromethane


Penoncello, S. , Lemmon, E. , Jacobsen, R. and Shan, Z. (2003), A Fundamental Equation for Trifluoromethane (R-23), J. Phys. & Chem. Ref. Data (JPCRD), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 14, 2024)
Created November 30, 2003, Updated October 12, 2021