Abstract

New experimental data on the pressure–density–temperature relationship of liquid octafluoropropane and two near azeotropic mixtures R218/R134a/isobutane and R125/R134a/n-butane are reported, obtained with a constant volume apparatus, which makes possible density measurements at subzero temperatures. The data cover temperatures from (203 to 353) K and at pressures up to 40 MPa for octafluoropropane and up to 50 MPa for the mixtures. The combined uncertainty at the 0.95 confidence level of the resultant density data is estimated to be 1 kg·m–3, that is, about 0.0008ρ for the octafluoropropane density ρ. The root-mean-square deviation of the obtained data for octafluoropropane from a Helmholtz free energy equation of state fitted to them is 0.56 kg·m–3 (0.0004ρ). For both mixtures, about 93 % of the experimental density data points lie within the interval ± 0.002ρ from the Lemmon–Jacobsen Helmholtz energy model for these mixtures.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.