A comparison of refrigerants in a two-stage ejector-expansion transcritical refrigeration cycle based on exergoeconomic and environmental analysis. (December 2017)

• Record Type: Journal Article
• Authors: Nemati, Arash; Nami, Hossein; Yari, Mortaza
• Is Part Of: International journal of refrigeration. Volume 84(2017)
• Page Start: 139
• Page End: 150
• Publication Date: 2017-12
• Subjects: Two-stage ejector-expansion -- Energy -- Exergy -- Exergoeconomic -- Environmental -- Refrigerants; Éjecteur-détente bi-étagé -- Énergie -- Éxergie -- Exergo-économique -- Environnement -- Frigorigènes; Refrigeration and refrigerating machinery -- Periodicals; 621.56
• DOI: 10.1016/j.ijrefrig.2017.09.002
• Languages: English
• ISSNs: 0140-7007

Abstract

Highlights: A comprehensive energy, exergy and exergoeconomic comparison is carried out. Carbon dioxide, ethane and nitrous oxide are selected as system refrigerants. The COP of system is maximized subject to the gas cooler and inter-stage pressures. Results indicate best refrigerant from thermodynamic and economic viewpoints. Abstract: A comprehensive energy, exergy, exergoeconomic and environmental comparison between carbon dioxide, ethane and nitrous oxide as the refrigerants of a two-stage ejector-expansion transcritical refrigeration cycle is carried out. All of the obtained results are attained by optimizing COP subject to gas cooler and intercooler pressures in different values of gas cooler and evaporator temperatures. It is observed that the compressors operating pressure and temperature levels in the cycle for ethane are lower than other refrigerants, which leads to higher system safety and lifetime. Furthermore, the highest COP and exergy efficiency in a wide range of gas cooler temperature belongs to the ethane. The nitrous oxide refrigerant has the lowest product unit cost, which is about 4.2% lower than that of the ethane refrigerant with the highest product unit cost. Therefore, ethane is the most preferable refrigerant from energy and exergy aspects and nitrous oxide is suitable based on exergoeconomic viewpoint.