IIR document

Pentafluoroethane (HFC125). Equation of state and transport properties.


Measurements of the thermal conductivity and PVT-data of R125 which is currently considered as substitute for R502 have been performed. 44 PVT points in the range 263-443 K and densities between 36 to 516 kg/m3 and 34 for vapour pressure at temperatures from 263 to 338 K have been obtained. Twenty-seven thermal conductivities for the vapour and liquid state were carried out at temperatures from 170 to 419 K for pressures up to 6 megapascals. The experimental uncertainties in temperature, pressure, density and thermal conductivity measurements have been estimated to be within 10 milliK, 0.08, 0.1 and 2-3% respectively. On the basis of these measurements the residual thermal conductivities were used to follow a single relationship versus the reduced density. The measured PVT-data have been to generate an equation of state for R125. The proposed equations can be used to obtain the thermophysical tables and charts.

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  • Original title: Pentafluoroethane (HFC125). Equation of state and transport properties.
  • Record ID : 1996-1452
  • Languages: English
  • Source: For a Better Quality of Life. 19th International Congress of Refrigeration.
  • Publication date: 1995/08/20
  • Document available for consultation in the library of the IIR headquarters only.


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