Vortex Tube Expansion Two-Stage Transcritical CO₂ Refrigeration Cycle

Abstract:

Use of vortex tube as an expansion device in transcritical CO₂ cycle could reduce the throttle loss and improve the coefficient of performance. In this paper, a vortex tube expansion two-stage transcritical CO₂ refrigeration cycle(VTTC) is established and compared to that of the two-stage transcritical CO₂ refrigeration cycle with throttle valve(TVTC). Thermodynamic analysis results indicate that there is also an optimum heat rejection pressure for the vortex tube cycle, and the COP improvement is 2.4%~16.3% at given conditions. Decrease in evaporation temperature or increase in gas-cooler outlet temperature decrease the COP, but the COP improvement will increase. The effect of cold mass fraction on the COP is negligible, but the COP improvement will increase fast with the increase of cold mass fraction.

• Periodical: Advanced Materials Research (Volumes 516-517)
• Pages: 1219-1223
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.516-517.1219
• Online since: May 2012
• Authors: Ying Fu Liu, Guang Ya Jin
• Keywords: Coefficient of Performance (COP), COP Improvement, Transcritical CO₂ Refrigeration Cycle, Two-Stage Compression, Vortex Tube

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