Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater

Influence of Refrigerant Charge Amount and EEV Opening on the Performance of a Transcritical CO2 Heat Pump Water Heater

Besides compressor rotary speed and parameters of water flowing through gas cooler and evaporator, refrigerant charge amount and electronic expansion valve (EEV) opening are two important parameters that have significant effects on the performance of a transcritical CO2 heat pump system. In this study, the effects of refrigerant charge amount on the performance of a transcritical CO2 heat pump ...

Performance Evaluation of a Two-Stage Compression Heat Pump System With Refrigerant Charge and EEV Opening

Experimental Investigation on the Influence of Refrigerant Charge on the Performance of Trans-critical CO2 Water-Water Heat Pump

For the environmentally aware, natural refrigerant such as CO2 is recommended and pursued by researchers for refrigerators. In this paper, a transcritical CO2 heat pump system was set up to investigate the influence of refrigerant charge on the performance of a small-sized heat pump water heater. The transcritical CO2 heat pump system was composed of a rotary compressor, a tube-in-tube evaporat...

Performance study on solar assisted heat pump water heater using CO2 in a transcritical cycle

This study reports the numerical analyses of a CO2 transcritical cycle on solar assisted heat pump water heating system in which evacuated tube U-pipe solar collector is utilized as an evaporator. This simulation model can predict operating characteristics for moderate meteorological conditions of North Dakota. The main purpose of this work is to simulate the overall performance of the heat pum...

Field Evaluation for Air-source Transcritical CO2 Heat Pump Water Heater with Optimal Pressure Control

Several optimal discharge pressure correlations for transcritical CO2 heat pump in literature have been discussed in this paper. Most of them are related to the ambient temperature, the evaporation temperature and the gas cooler outlet temperature. A revised optimal discharge pressure model as the function of ambient temperature and water outlet temperature is developed based on earlier experim...