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Numerical investigation of CO2 heat pump water heater performance.


This study presents a preliminary investigation of the performance of a Heat Pump Water Heater (HPWH) that uses CO2 as refrigerant. The global market of this technology is led by Japan and several units are being installed all around the world under different climates. The main challenge for an efficient spreading of this technology is to maintain the excellent performance of CO2 HPWH under a broad variety of weather conditions. A numerical model was developed to flexibly investigate the performance of the CO2 HPWH under various distributions of inlet air temperature at the evaporator and inlet water temperature in gas cooler. The simulation results are firstly compared with those from a general pinch point analysis. The Result show that the highest water temperature inlet and lowest air temperature inlet will produce lowest COP and Highest LCCP Contribution.

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Numerical Investigation of CO2 Heat Pump Water Heater Performance

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  • Original title: Numerical investigation of CO2 heat pump water heater performance.
  • Record ID : 30027931
  • Languages: English
  • Subject: Technology
  • Source: 14th IIR-Gustav Lorentzen Conference on Natural Refrigerants(GL2020). Proceedings. Kyoto, Japon, December 7-9th 2020.
  • Publication date: 2020/12/07
  • DOI:


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