Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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A Study on the Performance Characteristics of Water Heat Source Heat Pump System using CO2 Refrigerant

이산화탄소를 사용한 수열원 히트펌프 시스템의 성능 특성에 관한 실험적 연구

  • Chang, Keun-Sun (Department of Mechanical Engineering, Sunmoon University) ;
  • Kang, Hee-Jeong (Department of Mechanical Engineering, Sunmoon University) ;
  • Kim, Young-Jae (Department of Chemical and Biochemical Engineering, Sunmoon University)
  • Received : 2011.03.07
  • Accepted : 2011.08.11
  • Published : 2011.08.31
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Abstract

In this study, performance characteristics of a water source heat pump system using $CO_2$ as a refrigerant are investigated experimentally. Cooling and heating capacities and COP of the system are analyzed for various system performance variables such as refrigerant charge, expansion valve opening, compressor frequency and internal heat exchanger. Results show that optimum amount of refrigerant charge and expansion valve opening exists at maximum point of COP curve, and cooling capacity increases but COP decreases with the increase of compressor frequency. When the internal heat exchanger is installed, cooling capacity increases about 4.0% whereas heating capacity decreases about 0.89% compared to the case without internal heat exchanger.

본 논문에서는 $CO_2$ 냉매를 적용하는 수열원 히트펌프 시스템의 성능특성에 관하여 실험적으로 연구하였다. 냉매충진량, 전자팽창밸브 개도, 압축기 주파수, 내부열교환기의 유무 등 다양한 운전변수에 따라 냉방, 난방성능 및 COP 특성을 분석하였다. 실험결과는 2200g의 냉매충진량, 26%의 전자팽창밸브 개도비율에서 최고의 COP 곡선을 나타내고 있고 압축기 주파수의 증가에 따라 냉방능력은 증가하나 난방능력은 감소하는 것으로 나타났다. 이 시스템의 경우 내부열교환기를 포함할 경우 내부열교환기가 없을 경우에 비해 약 4%의 냉방 COP 증가되었고 난방 COP는 약 0.89%감소로 성능변화가 거의 나타나지 않았다.

Keywords

References

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