Energy improvements of CO2 transcritical refrigeration cycles using dedicated mechanical subcooling

[EN] In this work the possibilities of enhancing the energy performance of CO2 transcritical refrigeration systems using a dedicated mechanical subcooling cycle are analysed theoretically. Using simplified models of the cycles, the modification of the optimum operating conditions of the CO2 transcri...

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Detalles Bibliográficos
Autores: Llopis Doménech, Rodrigo, Cabello, Ramon, Sanchez, Daniel, Torrella Alcaraz, Enrique
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/99050
Acceso en línea:https://riunet.upv.es/handle/10251/99050
Access Level:acceso abierto
Palabra clave:CO2
Transcritical
Mechanical subcooling cycle
Energy efficiency
MAQUINAS Y MOTORES TERMICOS
Descripción
Sumario:[EN] In this work the possibilities of enhancing the energy performance of CO2 transcritical refrigeration systems using a dedicated mechanical subcooling cycle are analysed theoretically. Using simplified models of the cycles, the modification of the optimum operating conditions of the CO2 transcritical cycle by the use of the mechanical subcooling are analysed and discussed. Next, for the optimum conditions, the possibilities of improving the energy performance of the transcritical cycle with the mechanical subcooling are evaluated for three evaporating levels (5, 5 and 30 C) for environment temperatures from 20 to 35 C using propane as refrigerant for the subcooling cycle. It has been observed that the cycle combination will allow increasing the COP up to a maximum of 20% and the cooling capacity up to a maximum of 28.8%, being both increments higher at high evaporating levels. Furthermore, the results indicate that this cycle is more convenient for environment temperatures above 25 C. Finally, the results using different refrigerants for the mechanical subcooling cycle are presented, where no important differences are observed.