Functional Equations for Calculating the Properties of Low-GWP R1234ze(E) Refrigerant

Abstract

Legal requirements for the use of refrigerants increasingly restrict the use of high-global warming potential (GWP) refrigerants. As a result, there is a growing interest in natural refrigerants and in those belonging to the hydrofluoroolefins (HFO) class, which can be used on their own or in mixtures. One of them is the R1234ze(E) refrigerant, an alternative to the R134a refrigerant as well as being a component of numerous mixtures. The knowledge of thermodynamic and transport properties of refrigerants is required for the analysis and calculation of refrigeration cycles in refrigeration, air conditioning, or heating systems. The paper presents analytical equations for calculating the properties of the R1234ze(E) refrigerant in the state of saturation and in the subcooled liquid and superheated vapour regions that do not require numerical calculations and are characterised by small deviations. The Levenberg–Marquardt algorithm—one of the methods for non-linear least squares estimation—was used to develop them. A total of 26 equations were formulated. The formulated equations were statistically verified by determining absolute and relative deviations between the values obtained from CoolProp software and calculated values. The maximum relative deviation was not higher than 1% in any of them.

Identifying the performance and losses of a scroll compressor with vapour injection and R1234ze(E)

“…(6)-Equation. (7). The volumetric efficiency (η vol ) is defined as the ratio of the actual mass flow that enters the compressor to the theoretical one, calculated at the suction position by using the nominal volumetric flow rate 34 .…”

“…The performance indicators of the compressor are the volumetric and isentropic efficiency identified by Equation. (6) and Equation (7) as it was proposed in a characterization methodology of a vapour injection scroll compressor 34 . In Equation.…”

“…The most widely used HFO is R1234yf, charged in many automotive air conditioning systems as a replacement of R134a 6 . Another alternative to R134a for medium temperature applications is R1234ze(E) 5 , 7 with a GWP equal to 4, which is applied as a pure substance or a mixture component in many applications 8 . To evaluate its potential, Babiloni et al 9 tested a vapour compression system with an internal heat exchanger (IHX) operating with R1234yf and R1234ze(E).…”

Case Analysis of Heat Pump Integration in District Heating System

“…Atliekant šilumos surblio veikimo dinaminį modeliavimą, šaltnešio slėgio, temperatūros ir entalpijos vertės nustatomos taikant analitines formules (Zyczkowski et al, 2020).…”

Exergoeconomic Assessment of a Compact Electricity-Cooling Cogeneration Unit

“…Most research is still primarily focused on the use of R141b and R134a as working fluids [95], but the possibilities of using non-standard refrigerants must be considered (such as hydrofluoroolefins, either pure or mixed). Investigation and analysis of R463A as an alternative refrigerant to R404A was carried out successfully by Saengsikhiao et al [96], whileŻyczkowski et al [97] focused on R1234ze(E) due to the restrictions against the use of many refrigerants in the European Union since 2015.…”