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 Performance of a $CO_2$ Heat Pump Water Heater

$CO_2$ 급탕 열펌프의 성능 특성에 관한 실험적 연구

  • 이응찬 (고려대학교 기계공학과 대학원) ;
  • 백창현 (고려대학교 기계공학과 대학원) ;
  • 강훈 (고려대학교 기계공학과) ;
  • 김용찬 (고려대학교 기계공학과) ;
  • 조홍현 (조선대학교 기계공학과) ;
  • 조성욱 (삼성전자 DA연구소)
  • Published : 2009.06.10
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Abstract

The performance of a $CO_2$ heat pump water heater was measured with a variation of operating conditions such as refrigerant charge amount, outdoor temperature, compressor frequency, EEV opening, and water mass flow rate. The optimum refrigerant charge amount of the $CO_2$ system was 1800 g. At water mass flow rates of 75, 85, and 95 kg/h, the water heating temperatures were 74, 67, and $62^{\circ}C$ and COPs were 2.6, 2.8, and 3.0, respectively. Besides, the compressor frequency and water mass flow rate were adjusted to maintain the water heating temperature at $60^{\circ}C$ with the decrease of outdoor temperature. As the outdoor temperature decreased by $5^{\circ}C$, the compressor frequency increased beyond 60 Hz and the water mass flow rate decreased by 16.7%.

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References

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