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Equation of State for the Thermodynamic Properties of 1,1,2,2,3-Pentafluoropropane (R-245ca)



Eric W. Lemmon, Yong Zhou


hydrofluorocarbon (HFC) refrigerant, are presented. The properties are based on an equation of state (EOS) expressed in terms of the Helmholtz energy as a function of temperature and density, the formulation of which can be used for the calculation of all thermodynamic properties. The equation is valid for all liquid and vapor states of the fluid, and is valid from the triple point to 450 K, with pressures up to 10 MPa. Comparisons to experimental data are given to establish the accuracy of the EOS. The estimated uncertainty in the equation of state for density is 0.1% in the liquid phase between 243 K and 373 K with pressures up to 6.5 MPa; the uncertainties increase outside this range, and are unknown. The uncertainty in vapor-phase speed of sound is 0.1%. The uncertainty in vapor pressure is 0.2% between 270 K and 393 K. The uncertainties in other regions and properties are unknown due to a lack of experimental data.
International Journal of Thermophysics


equation of state, Helmholtz energy, R1234ze(E), thermodynamic properties


Lemmon, E. and Zhou, Y. (2015), Equation of State for the Thermodynamic Properties of 1,1,2,2,3-Pentafluoropropane (R-245ca), International Journal of Thermophysics, [online], (Accessed June 23, 2024)


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Created March 26, 2015, Updated June 2, 2021