A Fundamental Equation of State for 1,1,1,3,3-Pentafluoropropane (R-245fa)

Published

March 26, 2015

Author(s)

Ryo Akasaka, Yong Zhou, Eric Lemmon

Abstract

A new fundamental equation of state explicit in the Helmholtz energy is presented for 1,1,1,3,3 pentafluoropropane (R 245fa), based on recent experimental data for the vapor pressures, densities, and vapor sound speeds. The functional form now uses Gaussian bell-shaped terms, according to recent trends in the development of accurate equations of state. The independent variables of the equation of state are the temperature and density. The equation is valid for temperatures between the triple point (171.05 K) and 430 K, and for pressures up to 200 MPa. Estimated uncertainties in this range are 0.1 % for vapor pressures, 0.1 % for saturated liquid densities, 0.1 % for liquid densities below 70 MPa, 0.2 % for liquid densities at higher pressures, 0.3 % for vapor densities, 0.15 % for liquid sound speeds, and 0.1 % for vapor sound speeds. The uncertainties in the critical region are higher for all properties except vapor pressures. The equation shows reasonable extrapolation behavior at extremely low and high temperatures, and at high pressures.

Citation

Journal of Chemical and Engineering Data

Volume

44

Issue

1

Pub Type

Journals

Download Paper

https://doi.org/10.1063/1.4913493

Local Download

Keywords

equation of state, R 245fa, thermodynamic properties

Citation

Akasaka, R. , Zhou, Y. and Lemmon, E. (2015), A Fundamental Equation of State for 1,1,1,3,3-Pentafluoropropane (R-245fa), Journal of Chemical and Engineering Data, [online], https://doi.org/10.1063/1.4913493, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=917507 (Accessed October 31, 2024)