A comprehensive thermodynamic analysis of a refrigeration system with an internal heat exchanger was reported for four various refrigerants as an alternative to R134a. The preferred refrigerants in this paper have zero ozone-depleting potential and fairly low global warming potential value compared with reference R134a. These refrigerants are from both the HC group (R290 and R600a) and the HFO group (R1234yf and R1234ze(E)). Basically, the refrigeration system consists of a compressor, condenser, evaporator, expansion valve, and internal heat exchanger as well. Energy-exergy analyses and environmental impact assessments depending on the compressor energy consumptions are evaluated in the current study. The system performance was theoretically carried out at two different evaporation temperatures of 0 and -8°C. Based on the obtained results from this study, the highest performance was achieved in R600a from HC group refrigerants and R1234ze(E) from HFO group refrigerants. As compared with R134a, in the COP value of R600a an increase of 3.2% at the evaporation temperature of 0°C and 3.4% for the evaporation temperature of -8°C was achieved. On the other hand, the COP value for R1234yf was decreased by 2% at the evaporation temperature of 0°C and by 2.57% at the evaporation temperature of -8°C. Considering the CO₂ emissions, R600a was located at the first order in terms of the lowest CO₂ emissions and R1234ze(E) follows R600a. In conclusion, R600a presented the highest performance compared with R134a in a refrigeration system with an internal heat exchanger.

中文翻译：

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带有内部换热器的制冷系统中各种制冷剂的能源，能源和环境（3E）评估

据报道，对带有内部热交换器的制冷系统进行了全面的热力学分析，以替代R134a对四种制冷剂进行了分析。与参考R134a相比，本文中的首选制冷剂的臭氧消耗潜能为零，全球变暖潜能值相当低。这些制冷剂来自HC组（R290和R600a）和HFO组（R1234yf和R1234ze（E））。基本上，制冷系统由压缩机，冷凝器，蒸发器，膨胀阀和内部热交换器组成。在当前的研究中，对根据压缩机能耗而进行的能量-能量分析和环境影响评估进行了评估。理论上，系统性能是在0和-8°C的两种不同蒸发温度下进行的。根据这项研究的结果，使用HC组制冷剂的R600a和使用HFO组制冷剂的R1234ze（E）的性能最高。与R134a相比，R600a的COP值在0°C的蒸发温度下增加了3.2％，在-8°C的蒸发温度下增加了3.4％。另一方面，R1234yf的COP值在0°C的蒸发温度下降低了2％，在-8°C的蒸发温度下降低了2.57％。考虑CO R1234yf的COP值在0°C的蒸发温度下降低了2％，在-8°C的蒸发温度下降低了2.57％。考虑CO R1234yf的COP值在0°C的蒸发温度下降低了2％，在-8°C的蒸发温度下降低了2.57％。考虑CO_就2种排放而言，R600a在最低CO ₂排放方面位于第一位，而R1234ze（E）紧随R600a。总之，与带有内部热交换器的制冷系统中的R134a相比，R600a表现出最高的性能。