PREDICTION OF THERMAL CONDUCTIVITY OF R32, R125, R134a, R143a AND R152a AT ZERO DENSITY VIA SEMI-EMPIRICALLY-BASED ASSESSMENT

Abstract

The robust and efficient procedure is presented to calculate the transport properties, especially thermal conductivity coefficients, for gaseous state of difluoromethane (R32), pentafluoroethane (R125), 1, 1, 1, 2 tetrafluoroethane (R134a), 1, 1, 1 trifluoroethane (R143a) and 1, 1 difluoroethane (R152a) at zero density. The McLinden et al.'s1 approach of the extended corresponding states has been used for calculating the contribution of molecular degree of freedom to the thermal conductivity of these refrigerants. The Lennard–Jones 12-6 (LJ 12-6) potential energy function is used as the initial model potential required by the technique. The interaction potential energies from the inversion procedure reproduce the thermal conductivity coefficients commensurate to the best measurements.