The study on the effect of the internal heat exchanger on transcritical CO₂ ejector refrigeration system

Authors

WU Dongjiong, Industrial Technology Center 〔Innovation and Entrepreneurship Education Center〕, Shanghai Dianji University, Shanghai 201306, ChinaFollow
HU Jiang, School of Continuing Education, Shanghai Dianji University, Shanghai 201306, China
LI Yang, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China

Abstract

Objective: This study aimed to investigate the effect of internal heat exchanger on the performance of transcritical CO₂ two-stage compression/ejector refrigeration system. Methods: The simulation software was used to analyze the effects of the internal heat exchanger on the suction temperature, discharge temperature, specific work increment of the low-pressure compressor and system performance coefficient under different gas cooler outlet temperatures (25～45 ℃), high-pressure side discharge pressure (7.4～9.5 MPa), evaporation temperature (-40～-15 ℃) and intermediate pressure (3～5 MPa). Results: With the increase of intermediate pressure, the discharge temperature and specific work increment of the low-pressure compressor increased at a specific regenerative degree. However, with the increase in evaporation temperature, the discharge temperature and specific work increment of the low-pressure compressor gradually decrease. Under the control of this standard conditions, the coefficient of performance of the regenerative system is lower than that of the system without regenerative, and the energy efficiency of the regenerative system decreases with the increase of the regenerative degree. Conclusion: The suction temperature, discharge temperature, and specific work increment of the low-pressure compressor all rise significantly as the internal heat exchanger increases. However, the internal heat exchanger does not improve the performance of transcritical CO₂ two-stage compression/ejector refrigeration system.

Publication Date

1-30-2024

First Page

82

Last Page

89

DOI

10.13652/j.spjx.1003.5788.2023.80124

Recommended Citation

Dongjiong, WU; Jiang, HU; and Yang, LI (2024) "The study on the effect of the internal heat exchanger on transcritical CO₂ ejector refrigeration system," Food and Machinery: Vol. 40: Iss. 1, Article 12.
DOI: 10.13652/j.spjx.1003.5788.2023.80124
Available at: https://www.ifoodmm.cn/journal/vol40/iss1/12

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