*Article* **New HFC/HFO Blends as Refrigerants for the Vapor-Compression Refrigeration System (VCRS)**

**Bartosz Gil \*, Anna Szczepanowska and Sabina Rosiek**

> Department of Thermodynamics and Renewable Energy Sources, Faculty of Mechanical and Power Engineering, Wrocław University of Science and Technology, Wybrzeze Wyspia ´ ˙ nskiego 27, 50-370 Wrocław, Poland; aniaszczepanowska@gmail.com (A.S.); sabina.rosiek@pwr.edu.pl (S.R.)

**\*** Correspondence: bartosz.gil@pwr.edu.pl; Tel.: +48-71-320-4826

**Abstract:** In this work, which is related to the current European Parliament Regulation on restrictions affecting refrigeration, four new three-component refrigerants have been proposed; all were created using low Global Warming Potential(GWP) synthetic and natural refrigerants. The considered mixtures consisted of R32, R41, R161, R152a, R1234ze (E), R1234yf, R1243zf, and RE170. These mixtures were theoretically tested with a 10% step in mass fraction using a triangular design. The analysis covered two theoretical cooling cycles at evaporating temperatures of 0 and −30 ◦C, and a 30 ◦C constant condensing temperature. The final stage of the work was the determination of the best mixture compositions by thermodynamic and operational parameters. R1234yf–R152a–RE170 with a weight share of 0.1/0.5/0.4 was determined to be the optimal mixture for potentially replacing the existing refrigerants.

**Keywords:** hydrofluoroolefins; hydrofluorocarbons; refrigerants; low GWP

**Citation:** Gil, B.; Szczepanowska, A.; Rosiek, S. New HFC/HFO Blends as Refrigerants for the Vapor-Compression Refrigeration System (VCRS). *Energies* **2021**, *14*, 946. https://doi.org/10.3390/en14040946

Received: 17 December 2020 Accepted: 8 February 2021 Published: 11 February 2021

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