Application of Extended Corresponding States (ECS) and Residual Entropy Scaling (RES) Techniques for Modeling Viscosity of cis -1,3,3,3-Tetrafluoropropene (R1234ze(Z)) with Revised Experimental Data

This paper focuses on the empirical modeling for viscosities of a hydrofluoroolefin refrigerant, R1234ze(Z), which is considered an environmentally friendly alternative to hydrofluorocarbons. The refrigerant has favorable thermophysical properties and a low global warming potential. A new fundamental equation of state (EoS) for R1234ze(Z) was developed in 2019, which aligns with the recent trends of developing accurate fundamental equations of state. However, previously published experimental viscosity data were reported using an old equation of state of the fluid. In this paper, the revised experimental viscosity data based on the latest EoS has been reported for R1234ze(Z). Additionally, the viscosity model of this fluid is presented using the extended corresponding states (ECS) and modified fluid-specific residual entropy scaling (RES) techniques. By using the adjustable parameters, the ECS and the modified fluid-specific RES transport equations can represent the experimental data within reported uncertainties. The average absolute deviations (AAD) for viscosity were found to be 1.40% and 1.65% using the ECS and the RES method, respectively. This study also highlights the importance of using the most accurate EoS when reporting experimental data, especially when formulating transport property models based on these techniques.