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Performance of ejector cooling systems using low ecological impact refrigerants / Raul Roman in International journal of refrigeration, Vol. 34 N° 7 (Novembre 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 7 (Novembre 2011) . - pp. 1707-1716 Titre : Performance of ejector cooling systems using low ecological impact refrigerants Titre original : Performance des systèmes de refroidissement à éjecteur employant des frigorigènes exerçant un faible impact sur l'environnement Type de document : texte imprimé Auteurs : Raul Roman, Auteur ; Jorge I. Hernandez, Auteur Année de publication : 2011 Article en page(s) : pp. 1707-1716 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Cooling  Ejector  system  Performance  Hydrocarbon  R134a  R152a Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The theoretical behaviour of an ejector cooling system, using as working fluids propane, butane, isobutane, R152a and R134a, is obtained. The ejector works as a thermo-compressor that is simulated with a validated one-dimensional mathematical model, whose errors are lower than 6%. For a system unitary cooling capacity, a parametric study is carried out varying the generation, condensation and evaporation temperatures. From the obtained data, a complete analysis of the system performance can be achieved when the ejector and system operation parameters are considered. The best performance corresponds to the system using propane, because has the highest system coefficient of performance and its ejector has the maximum entrainment ratio value, the least area ratio value and the highest efficiency value. The considered generation temperature ranging from 70 °C to 95 °C is appropriate for low-grade energy sources assisting thermal cooling systems. After this system performance, come those in which R152a and R134a are employed, with isobutane and butane at the end. The obtained results represent potential design points of an efficient ejector cooling system operation, because to each combination of the above mentioned temperatures corresponds one and only one ejector geometry. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711000697 [article] Performance of ejector cooling systems using low ecological impact refrigerants = Performance des systèmes de refroidissement à éjecteur employant des frigorigènes exerçant un faible impact sur l'environnement [texte imprimé] / Raul Roman, Auteur ; Jorge I. Hernandez, Auteur . - 2011 . - pp. 1707-1716. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 7 (Novembre 2011) . - pp. 1707-1716 Mots-clés : Cooling  Ejector  system  Performance  Hydrocarbon  R134a  R152a Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The theoretical behaviour of an ejector cooling system, using as working fluids propane, butane, isobutane, R152a and R134a, is obtained. The ejector works as a thermo-compressor that is simulated with a validated one-dimensional mathematical model, whose errors are lower than 6%. For a system unitary cooling capacity, a parametric study is carried out varying the generation, condensation and evaporation temperatures. From the obtained data, a complete analysis of the system performance can be achieved when the ejector and system operation parameters are considered. The best performance corresponds to the system using propane, because has the highest system coefficient of performance and its ejector has the maximum entrainment ratio value, the least area ratio value and the highest efficiency value. The considered generation temperature ranging from 70 °C to 95 °C is appropriate for low-grade energy sources assisting thermal cooling systems. After this system performance, come those in which R152a and R134a are employed, with isobutane and butane at the end. The obtained results represent potential design points of an efficient ejector cooling system operation, because to each combination of the above mentioned temperatures corresponds one and only one ejector geometry. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700711000697