<p>This work introduces an experimental investigation of a small-scale vapor compression refrigeration system initially intended for R134a, in light of research on energy and exergetic study. The investigation compares system performance to low-global warming potential (GWP) refrigerants R513A (GWP <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$\approx $</EquationSource> <EquationSource Format="MATHML"><math> <mo>≈</mo> </math></EquationSource> </InlineEquation> 573) and R1234yf, an ultra-low-GWP refrigerant (GWP <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$\approx $</EquationSource> <EquationSource Format="MATHML"><math> <mo>≈</mo> </math></EquationSource> </InlineEquation> 4). This study defines “low-GWP” refrigerants as those with a GWP below 700, according to California Air Resources Board (CARB) and Air Conditioning, Heating and refrigeration Institute (AHRI) criteria. Each refrigerant was evaluated at 250 g to promote the switch to ecologically friendly refrigerants and boost system efficiency. They were assessed for feasibility and performance in existing installations. A retrofit feasibility analysis of R513A and R1234yf was carried out in this study by using the change in the heating demand. Heating load varies across levels ranging from Level 1: 24 W, Level 2: 96 W, Level 3: 216 W, Level 4: 388 W, Level 5: 615 W, Level 6: 885 W, to Level 7: 1218 W. When it comes to oil compatibility, the study takes R1234yf in particular into consideration. A thermodynamic model has been created for investigation and simulation using the matrix laboratory (MATLAB) program. The test results showed that the system works well with both R134a and R513A at a charge of 250g. The research demonstrated that R134a and R513A are compatible with polyester (POE) oil inside the same system. On the other hand, when the same system was charged with an equivalent mass of R1234yf, the system did not work effectively because of the incompatibility between the oil and the R1234yf. In addition, as compared to the other refrigerants that were evaluated, R1234yf showed a substantially lower level of performance while using polyalkylene glycol (PAG) oil. R1234yf demonstrated the greatest exergy destruction at 2.28 W, followed by R513A at 1.93 W and R134a at 1.64 W. Exergy destruction for R1234yf was 28.07% greater than that of R134a and 15.35% greater than R513A. R134a demonstrated the highest exergetic efficiency at 35.81%, marginally surpassing R513A at 34.54% and significantly exceeding R1234yf at 24.43%, thereby indicating superior thermodynamic performance. R513A can be used instead of R134a because it works with POE oil, but R1234yf needs to have its oil changed and its system redesigned.</p>

Experimental investigation of drop-in substitutes for R134a in a small-scale vapor compression refrigeration system utilizing R513A and R1234yf with MATLAB analysis

期刊论文
发表日期：

2026年7月18日

查看全文

Jyoti Soni,
Alok Chaube,
P. K. Jhinge

摘要

This work introduces an experimental investigation of a small-scale vapor compression refrigeration system initially intended for R134a, in light of research on energy and exergetic study. The investigation compares system performance to low-global warming potential (GWP) refrigerants R513A (GWP $\approx $ $\approx$ 573) and R1234yf, an ultra-low-GWP refrigerant (GWP $\approx $ $\approx$ 4). This study defines “low-GWP” refrigerants as those with a GWP below 700, according to California Air Resources Board (CARB) and Air Conditioning, Heating and refrigeration Institute (AHRI) criteria. Each refrigerant was evaluated at 250 g to promote the switch to ecologically friendly refrigerants and boost system efficiency. They were assessed for feasibility and performance in existing installations. A retrofit feasibility analysis of R513A and R1234yf was carried out in this study by using the change in the heating demand. Heating load varies across levels ranging from Level 1: 24 W, Level 2: 96 W, Level 3: 216 W, Level 4: 388 W, Level 5: 615 W, Level 6: 885 W, to Level 7: 1218 W. When it comes to oil compatibility, the study takes R1234yf in particular into consideration. A thermodynamic model has been created for investigation and simulation using the matrix laboratory (MATLAB) program. The test results showed that the system works well with both R134a and R513A at a charge of 250g. The research demonstrated that R134a and R513A are compatible with polyester (POE) oil inside the same system. On the other hand, when the same system was charged with an equivalent mass of R1234yf, the system did not work effectively because of the incompatibility between the oil and the R1234yf. In addition, as compared to the other refrigerants that were evaluated, R1234yf showed a substantially lower level of performance while using polyalkylene glycol (PAG) oil. R1234yf demonstrated the greatest exergy destruction at 2.28 W, followed by R513A at 1.93 W and R134a at 1.64 W. Exergy destruction for R1234yf was 28.07% greater than that of R134a and 15.35% greater than R513A. R134a demonstrated the highest exergetic efficiency at 35.81%, marginally surpassing R513A at 34.54% and significantly exceeding R1234yf at 24.43%, thereby indicating superior thermodynamic performance. R513A can be used instead of R134a because it works with POE oil, but R1234yf needs to have its oil changed and its system redesigned.