Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Experimental Study on the Cooling Performance Improvement of a Two-stage Compression $CO_2$ Cycle

2단압축 이산화탄소 사이클의 냉방성능 향상 특성에 대한 실험적 연구

  • Published : 2006.10.01
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Abstract

A $CO_2$ system using the two-stage compression cycle was tested by varying $1^{st}-2^{nd}$ compressor frequencies in the cooling mode. To improve the cooling performance of the two-stage compression $CO_2$ cycle, the following cycle options were applied: a basic cycle, a cycle with an intercooler, a cycle with an IHX (internal heat exchanger), and a cycle with an intercooler and IHX. The cycle with the intercooler-IHX showed the highest cooling capacity improvement among the cycle options at all compressor frequencies. The cycle with the intercooler, the cycle with the IHX, and the cycle with the intercooler-IHX improved the cooling COP by 7, 12, and 15%, respectively, over the basic $CO_2$ cycle when the compressor frequencies for the first and second compressors were 50 Hz and 30 Hz, respectively. In addition, the applications of the selected cycle options enhanced system reliability.

Keywords

References

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