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Analytical Study on the Heating Performance Improvement of a CO2 Heat Pump Using Vapor Injection

가스인젝션을 적용한 이산화탄소 열펌프의 난방성능 향상에 관한 해석적 연구

  • Jung, Jongho (Graduate School of Mechanical Engineering, Korea University) ;
  • Baek, Changhyun (Graduate School of Mechanical Engineering, Korea University) ;
  • Heo, Jaehyeok (Department of Mechanical Engineering, Korea University) ;
  • Kim, Yongchan (Department of Mechanical Engineering, Korea University)
  • 정종호 (고려대학교 기계공학과 대학원) ;
  • 백창현 (고려대학교 기계공학과 대학원) ;
  • 허재혁 (고려대학교 기계공학과) ;
  • 김용찬 (고려대학교 기계공학과)
  • Received : 2012.08.10
  • Published : 2012.11.10

Abstract

In this study, a simulation model for a $CO_2$ heat pump using vapor injection was developed and validated. It was used to predict the improvement of the heating performance of the $CO_2$ heat pump at various operating conditions. The simulation results showed consistent results with the measured data. The heating performances of the vapor injection and non-injection heat pumps were compared by varying the outdoor temperature and compressor frequency. The heating capacity of the vapor injection heat pump was 40% higher than that of the non-injection heat pump at the outdoor temperature of $-8^{\circ}C$. The performance of the vapor injection heat pump was consistently higher than that of the non-injection heat pump even when the compressor frequency was reduced to 35 Hz at the outdoor temperature of $-3^{\circ}C$.

Keywords

References

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