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 CO2 Heat Pump Water Heater under Various Operating Conditions

이산화탄소 급탕 열펌프의 운전조건에 따른 성능 특성에 관한 실험적 연구

  • Sohn, Dong-Jin (Graduate School of Mechanical Engineering, Korea University) ;
  • Baek, Chang-Hyun (Graduate School of Mechanical Engineering, Korea University) ;
  • Heo, Jae-Hyeok (Department of Mechanical Engineering, Korea University) ;
  • Kang, Hoon (Department of Mechanical Engineering, Korea University) ;
  • Kim, Yong-Chan (Department of Mechanical Engineering, Korea University)
  • 손동진 (고려대학교 기계공학과 대학원) ;
  • 백창현 (고려대학교 기계공학과 대학원) ;
  • 허재혁 (고려대학교 기계공학과) ;
  • 강훈 (고려대학교 기계공학과) ;
  • 김용찬 (고려대학교 기계공학과)
  • Received : 2010.12.08
  • Accepted : 2011.02.23
  • Published : 2011.04.10
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Abstract

In this study, the steady state performance of a $CO_2$ heat pump water heater was measured with a variation of operating conditions such as refrigerant charge amount, compressor frequency, EEV opening, and water mass flow rate. Transient state performance tests were also conducted to investigate major system effects associated with the interaction between the $CO_2$ heat pump water heater and the water tank. Optimum refrigerant charge amount for the system was 1600 g. At compressor frequencies of 50 Hz and 60 Hz, water mass flow rates of 95 kg/h and 105 kg/h, and EEV opening of 8% and 16%, the water heating temperatures were $65^{\circ}C$ and $68^{\circ}C$ and COPs were 3.0 and 2.8, respectively. In the transient condition, the instantaneous COP decreased with an increase in the inlet water temperature.

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References

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