Next Article in Journal
District Cooling Versus Individual Cooling in Urban Energy Systems: The Impact of District Energy Share in Cities on the Optimal Storage Sizing
Next Article in Special Issue
Perspectives on Consumer Habits with Domestic Refrigerators and Its Consequences for Energy Consumption: Case of Study in Guanajuato, Mexico
Previous Article in Journal
Coal Strength Development with the Increase of Lateral Confinement
Previous Article in Special Issue
Control Strategies in Multi-Zone Air Conditioning Systems
Version is current.

Open AccessFeature PaperReview

Multi-Ejector Concept: A Comprehensive Review on its Latest Technological Developments

1
Department of Energy and Process Engineering, NTNU Norwegian University of Science and Technology, Kolbjørn Hejes vei 1D, 7491 Trondheim, Norway
2
Department of Thermal Energy, SINTEF Energy Research, Kolbjørn Hejes vei 1A, 7491 Trondheim, Norway
3
Construction Technology Institute, CNR National Research Council of Italy, Corso Stati Uniti 4, 35127 Padua, Italy
4
Danfoss A/S, Nordborgvej 81, 6430 Nordborg, Denmark
*
Author to whom correspondence should be addressed.
Energies 2019, 12(3), 406; https://doi.org/10.3390/en12030406
Received: 28 December 2018 / Revised: 24 January 2019 / Accepted: 25 January 2019 / Published: 28 January 2019
  |  
PDF [13084 KB, uploaded 28 January 2019]
  |  

Abstract

The adoption of the EU F-Gas Regulation 517/2014 and the resulting development of the multi-ejector concept have led carbon dioxide to take center stage as the sole refrigerant (R744) in several applications. Therefore, a knock-on effect on the number of supermarkets relying on “CO2 only” refrigeration systems has been experienced. Additionally, a global consensus of commercial multi-ejector based R744 units is also intensifying as a consequence of both the promising results obtained and the other measures in force for environment preservation. Furthermore, the multi-ejector concept is expected to offer significant energy savings in other high energy-demanding buildings (e.g., hotels, gyms, spas) as well, even in warm climates. In this investigation, the evolution of R744 ejector supported parallel vapor compression system layouts for food retail applications was summed up. Furthermore, their technological aspects, the results related to the main theoretical assessments and some relevant field/laboratory measurements were summarized. Also, the experience gained in the adoption of the multi-ejector concept in transcritical R744 vapor-compression units aimed at other energy intensive applications was presented. Finally, the persistent barriers needing to be overcome as well as the required future work were brought to light. View Full-Text
Keywords: air conditioning; chiller; CO2; commercial refrigeration; heat pump; heat recovery; industrial refrigeration; R744; transcritical vapor-compression system; two-phase ejector air conditioning; chiller; CO2; commercial refrigeration; heat pump; heat recovery; industrial refrigeration; R744; transcritical vapor-compression system; two-phase ejector
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Gullo, P.; Hafner, A.; Banasiak, K.; Minetto, S.; Kriezi, E.E. Multi-Ejector Concept: A Comprehensive Review on its Latest Technological Developments. Energies 2019, 12, 406.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Energies EISSN 1996-1073 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top