Ejector refrigeration is a promising technology to reduce primary energy consumption for building cooling. Unfortunately, a change in the design criteria (i.e., geometry, working fluid, operating conditions) influences the system performance owing to variations in the local fluid dynamic phenomena at the “local-scale”. For this reason, a general agreement on ejector performance is far from being reached. In addition, a general assessment of ejector performance is even more challenging when considering the recent regulations concerning the working fluids, which are going to phase-out most of the refrigerants commonly used in refrigeration and air conditioning systems. Despite there are different options to replace them, no refrigerant has yet imposed. This paper contributes to the discussion on the screening of working fluids, using a previously-validated lumped parameter model. The modelling approach has been applied to sub-critic ejector refrigeration systems and some alternatives to high GWP refrigerants are considered. The influence of the generator, the evaporator and the condenser temperatures over the ejector performance, for the different working fluids, have been presented and commented. The results are comments in terms of entrainment ratio and coefficient of performance, to provide indications and guidelines for refrigerant selection in prospective ejector refrigeration systems

A Screening of Low-GWP Refrigerant for Ejector Refrigeration

Besagni G.;Nesa R.
2018-01-01

Abstract

Ejector refrigeration is a promising technology to reduce primary energy consumption for building cooling. Unfortunately, a change in the design criteria (i.e., geometry, working fluid, operating conditions) influences the system performance owing to variations in the local fluid dynamic phenomena at the “local-scale”. For this reason, a general agreement on ejector performance is far from being reached. In addition, a general assessment of ejector performance is even more challenging when considering the recent regulations concerning the working fluids, which are going to phase-out most of the refrigerants commonly used in refrigeration and air conditioning systems. Despite there are different options to replace them, no refrigerant has yet imposed. This paper contributes to the discussion on the screening of working fluids, using a previously-validated lumped parameter model. The modelling approach has been applied to sub-critic ejector refrigeration systems and some alternatives to high GWP refrigerants are considered. The influence of the generator, the evaporator and the condenser temperatures over the ejector performance, for the different working fluids, have been presented and commented. The results are comments in terms of entrainment ratio and coefficient of performance, to provide indications and guidelines for refrigerant selection in prospective ejector refrigeration systems
Proceedings of the 21st Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution
Ejector
File in questo prodotto:
File Dimensione Formato  
2018_PRES_BesagniCrociNesa_Ejector.pdf

Accesso riservato

: Publisher’s version
Dimensione 516.5 kB
Formato Adobe PDF
516.5 kB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11311/1188516
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact