Performance mapping of the R744 ejectors for refrigeration and air conditioning supermarket application: A hybrid reduced-order model

Michal Haida, Jacek Smolka, Armin Hafner, Ziemowit Ostrowski, Michał Palacz, Kenneth B. Madsen, Sven Försterling, Andrzej J. Nowak and Krzysztof Banasiak

Energy, 2018, vol. 153, issue C, 933-948

Abstract: The continuous derivation of the ambient temperature and cooling demand in CO2 refrigeration and air-conditioning systems equipped with multi-ejector modules for supermarkets requires the analysis of the fixed ejector utilisation in a very wide range of the operational envelope. Therefore, performance mapping of the four R744 ejectors installed in the multi-ejector pack was performed. The investigations of a single ejector's work were performed based on the proposed hybrid reduced-order model to predict the performance of each ejector under arbitrary operating conditions. The proposed model was validated and generated by use of the experimental data together with the computational fluid dynamic model results. The ejector efficiency mapping indicated the area of the best ejector performance in the range from approximately 50 bar–100 bar. The mass entrainment ratio of all four ejectors was presented for different ambient temperatures and the pressure lift. An area of the mass entrainment ratio greater than 0.3 was obtained by each ejector at ambient temperature above approximately 15 °C for pressure lift below 10 bar. The approximation functions of the ejector pressure lift in terms of the ambient temperature for air-conditioning operating conditions to reach the best efficiency of each ejector are proposed.

Keywords: Carbon dioxide; Refrigeration system; Air-conditioning; Two-phase ejector; Reduced-order model; Performance mapping (search for similar items in EconPapers)
Date: 2018
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (9)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544218306959
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:153:y:2018:i:c:p:933-948

DOI: 10.1016/j.energy.2018.04.088

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().