{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T14:59:45Z","timestamp":1769007585369,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,8,23]],"date-time":"2022-08-23T00:00:00Z","timestamp":1661212800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>This study examines the potential impact of the different ejector profiles on the CO2 transcritical cooling system to highlight the contribution of the multi-ejector in the system performance improvement. The research compares the implementation of an ejector-boosted CO2 refrigeration system over the second-generation layout at a motive flow temperature of 35 \u00b0C and discharge pressure of 90 bar to account for the transcritical operation mode. The result revealed a significant energy saving by reducing the input power to the maximum of 8.77% when the ejector was activated. Furthermore, the multi-ejector block could recover up to 25.4% of the expansion work losses acquired by both ejector combinations VEJ1 + 2. In addition, the behavior of the multi-ejector geometries and operation conditions greatly influence the system exergy destruction. The analysis shows a remarkable lack of exergy destruction during the expansion process by deploying the ejector in parallel with the HPV.<\/jats:p>","DOI":"10.3390\/e24091173","type":"journal-article","created":{"date-parts":[[2022,8,23]],"date-time":"2022-08-23T21:05:12Z","timestamp":1661288712000},"page":"1173","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Evaluation of Various Ejector Profiles on CO2 Transcritical Refrigeration System Performance"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4187-3655","authenticated-orcid":false,"given":"Anas F. A.","family":"Elbarghthi","sequence":"first","affiliation":[{"name":"Department of Applied Mechanics, Faculty of Mechanical Engineering, Technical University of Liberec, Stdentsk\u00e1 1402\/2, 46117 Liberec, Czech Republic"}]},{"given":"V\u00e1clav","family":"Dvo\u0159\u00e1k","sequence":"additional","affiliation":[{"name":"Department of Applied Mechanics, Faculty of Mechanical Engineering, Technical University of Liberec, Stdentsk\u00e1 1402\/2, 46117 Liberec, Czech Republic"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/j.pecs.2003.09.002","article-title":"Fundamental process and system design issues in CO2 vapor compression systems","volume":"30","author":"Kim","year":"2004","journal-title":"Prog. Energy Combust. Sci."},{"key":"ref_2","unstructured":"Chasserot, M., Masson, N., Jia, H., Burkel, S., Maratou, A., and Ska\u010danov\u00e1, K. (2022, August 18). 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