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• Experimental thermal conductivity data of R1234ze(Z) has been reported. • Empirical models of thermal conductivity of R1234ze(Z) was carried with the new data using ECS and RES method. • Modification of RES method has been adopted to make it independent of ECS method. • Adjustable parameters of both ECS and RES methods have been reported. • Models presented show very good agreement with experimental data. This article represents the empirical modeling for thermal conductivity of cis-1,3,3,3-tetrafluoropropene (R1234ze(Z)) with new experimental measurements conducted in liquid and vapor phases using the well-established transient hot-wire method. These new experimental data, covering a temperature range of 313 to 414 K for liquid and 354 to 452 K for vapor phase at a pressure range of 0.20 to 4.0 MPa, have an expanded uncertainty of less than 2.17% for liquid and 2.41 % for vapor measurements at a 95 % confidence level (k = 2). The thermal conductivity model of this fluid is presented using the extended corresponding states (ECS) and modified fluid specific residual entropy scaling (RES) techniques with the help of recently published respective viscosity models. Using the adjustable parameters found during the modeling process, the extended corresponding states and the residual entropy scaling technique model equations can represent the experimental data within reported uncertainties. Furthermore, the average absolute deviations for thermal conductivity were found to be 0.96 % and 0.72 % using the ECS and the RES methods, respectively. [ABSTRACT FROM AUTHOR]

The cis-1-chloro-2,3,3,3-tetrafluoropropene (R-1224yd(Z)) is a new low global warming potential promising working fluid in high temperature heat pumps and organic Rankine cycle. In this study, the thermal conductivity was measured in the temperatures from 317 to 416 K with pressures from 1.0 to 4.0 MPa at liquid phase and from 376 to 453 K with pressures from 0.2 to 1.5 MPa at vapor phase. The combined standard uncertainties of thermal conductivity measurements were estimated to be less than ±2.1% at liquid and ±2.3% at vapor phases. On the other hand, the viscosity was measured over the temperature range of 303–424 K at liquid and from 394 to 475 K at vapor phase up to 4.0 MPa. The combined standard uncertainties were estimated to be less than ±2.95% at liquid and ±3.0% at vapor phases. Moreover, correlations were developed at saturation condition. [ABSTRACT FROM AUTHOR]

• HFE-356mmz is a low global warming working fluid. • Thermal conductivity measurements are presented using transient hot wires method. • Kinematic viscosity measurements are reported using tandem capillary tubes method. • Correlations have developed for saturation liquid and vapor. Hydrofluoroether 1,1,1,3,3,3-hexafluoro-2-methoxypropane (HFE-356mmz) is a promising candidate of low global warming working fluid in high-temperature heat pumps and organic Rankine cycle. In this study, the thermal conductivity was measured by using a transient hot wire method in the conditions of temperature from 319 to 462 K and pressure from 0.5 to 4.0 MPa for the liquid phase, and temperature from 393 to 452 K and pressure from 0.18 to 1.04 MPa for vapor phase. The combined standard uncertainties of thermal conductivity measurements were estimated to be less than 2.3% at liquid and 2.6% at vapor phases. On the other hand, the kinematic viscosity was measured by using tandem the capillary tubes method over the temperature range of 313–454 K for liquid and from 393 to 475 K for vapor phase up to 4.00 MPa. The uncertainties in liquid and vapor phases were estimated to be less than 2.9% and 3.0%, respectively. Also, correlations have been developed for saturated liquid and vapor. [ABSTRACT FROM AUTHOR]

In this work, thermal conductivity of a refrigerant trans -1‑chloro‑3,3,3-trifluoropropene (R-1233zd(E)) was measured and simplified correlations at saturated state were proposed. R-1233zd(E) is an unsaturated hydrochlorofluoroolefin and it is considered as an alternative working fluid due to its preferable properties. The thermal conductivity of R-1233zd(E) was measured by a well-established transient hot-wire method at temperatures from 313 to 433 K and 334 to 474 K for the liquid and vapor phases, respectively for pressures up to 4.0 MPa. Experimental values of thermal conductivity were compared to predicted values from conventional correlations as well as proposed simplified correlations for saturation condition. The estimated combined standard uncertainty of thermal conductivity of R-1233zd(E) was found ± 2.17% for liquid and ± 2.52% for vapor at a confidence level of 95%. [ABSTRACT FROM AUTHOR]

A Hydro-Fluoro-Olefin refrigerant cis-1,1,1,4,4,4-hexafluoro-2-butene (R-1336mzz(Z)) has low global warming potentials and it is considered as a potential working fluid for high temperature heat pump and Organic Rankine Cycle. Thermophysical properties of this fluid are necessary to be used in practical system. In this work, thermal conductivity of R-1336mzz(Z) is measured using a well-known transient hot wire method. A polarization voltage of 6 V was applied to minimize the effect of polarity. The thermal conductivity of liquid and gaseous R-1336mzz(Z) is measured in the temperature which ranges from 314 K to 435 K and 321 K to 496 K, respectively at a pressure up to 4 MPa and proposed simplified correlations. Total standard uncertainties of thermal conductivity measurements in liquid and gas phase were estimated to be less than ±2.07% and ±2.26% respectively and near the critical temperature, the uncertainty increases to ±3.40%. [ABSTRACT FROM AUTHOR]