A Study on the Operating Performance of a Cascade Heat Pump

캐스케이드 열펌프시스템의 운전 특성에 관한 연구

  • Chang, Ki-Chang (Geothermal Research Group, Korea Institute of Energy Research(KIER)) ;
  • Baik, Young-Jin (Geothermal Research Group, Korea Institute of Energy Research(KIER)) ;
  • Ra, Ho-Sang (Geothermal Research Group, Korea Institute of Energy Research(KIER)) ;
  • Kim, Ji-Young (Department of Mechanical Engineering, Korea University) ;
  • Lee, Jea-Hun (Department of Mechanical Engineering, Hanbat University)
  • 장기창 (한국에너지기술연구원(KIER)) ;
  • 백영진 (한국에너지기술연구원(KIER)) ;
  • 나호상 (한국에너지기술연구원(KIER)) ;
  • 김지영 (고려대학교 기계공학과 대학원) ;
  • 이재훈 (한밭대학교 기계공학과 대학원)
  • Published : 2009.06.01

Abstract

The purpose of this study is to investigate the performance of a water heat source cascade heat pump system R717(Ammonia) is used for a low-stage working fluid while R134a is for a high-stage. In order to gain a high temperature supply water in winter season, the system is designed to perform a cascade cycle. In this study, two experiments were carried out. One is a system starting test from the low load temperature of $10^{\circ}C$. The other is a system performance investigation over the R717 compressor capacity changes. Experimental results show that when it starts from the low load temperature, the suction temperature of the low-stage compressor is higher than that of a high-stage. The system performance increases when a water source temperature or a low-stage compressor rotational frequency goes higher.

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