THERMAL-CONDUCTIVITY AND PVT MEASUREMENTS OF PENTAFLUOROETHANE (REFRIGERANT HFC-125)

By means of the transient and steady-state coaxial cylinder methods, the thermal conductivity of pentafluoroethane was investigated at temperatures from 187 to 419 K and pressures from atmospheric to 6.0 MPa. The estimated uncertainty of the measured results is +/-(2-3)%. The operation of the experimental apparatus was validated by measuring the thermal conductivity of R22 and R12. Determinations of the vapor pressure and PVT properties were carried out by a constant-volume apparatus for the temperature range 263 to 443 K, pressures up to 6 MPa, and densities from 36 to 516 kg m(-3). The uncertainties in temperature, pressure, and density are less than +/- 10 mK, +/-0.08%, and +/-0.1%, respectively.