ICOPE-15-1051 Effect of wave height and its orientation on heat transfer performance of plate condenser used for heat pump water heater

The water mass flow and air relative humidity on the performance of air-source heat pump water heater was discussed in this paper. The results show that the energy efficiency of heat pump water heater is improved by correct the water mass flow and discharge pressure can be reduced, the value of the condenser temperature difference between the import and export of water also can be reduced. Increasing the air relative humidity, the more condensated water on evaporator surface effective, the greater the wetting area. In addition, the heat transfer of latent heat can be increased by the growth of air side and refrigerant side heat transfer coefficient.

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Design and Experimental Research of Gas Cooler for CO2 Heat Pump Water Heater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.156-157.1161 ◽

2010 ◽

Vol 156-157 ◽

pp. 1161-1164

Author(s):

Ye Feng Liu ◽

Guo Dong Gong ◽

Xi Chen

Keyword(s):

Heat Transfer ◽

Heat Pump ◽

Hot Water ◽

Global Environment ◽

Heat Transfer Characteristics ◽

Water Heater ◽

Working Pressure ◽

Heat Pump Water Heater ◽

Double Pipe ◽

Pipe Heat

The advantages of CO2 Heat Pump water heater include: CO2 is one of natural refrigerants and does not affect the global environment as many other HFCs refrigerants; CO2 heat pump water heater can produce hot water up to 90 ,which is higher than HFCs heat pump water heater(about 55 ).So the application of CO2 Heat Pump water heater is potential. But the Working pressure of CO2 Heat Pump Water Heater is about 9~12Mpa and is 3-5times of HFCs heat pump water heater’. Gas cooler is one of important part for CO2 heat pump water heater, and it must meet the needs of not only pressurization but also heat transfer. So it is important to design gas cooler correctly. In the paper, one system of CO2 Trans-critical Cycle Heat Pump Water Heater is designed, and double-pipe gas cooler is designed The heat transfer characteristics of CO2 in gas cooler with water in double-pipe heat exchanger was experimentally investigated. Experimental results showed that the gas cooler can meet the need of trans-critical CO2 cycle heat pump water heater. All the work is valuable for the application of CO2 heat pump water heater.

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Study of Circuit Number on the Evaporator in CO2 Heat Pump Water Heater

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.2266 ◽

2011 ◽

Vol 71-78 ◽

pp. 2266-2270 ◽

Cited By ~ 1

Author(s):

Kang Liu ◽

Jing Lv ◽

Song Bo Zhang ◽

Jie Yang

Keyword(s):

Heat Transfer ◽

Carbon Dioxide ◽

Heat Transfer Coefficient ◽

Transfer Coefficient ◽

Heat Pump ◽

Temperature Difference ◽

Water Heater ◽

Overall Heat Transfer Coefficient ◽

Heat Pump Water Heater ◽

Simulation Package

In the design of a carbon dioxide heat pump water heater evaporator, the effect of the circuit number on the evaporator is investigated numerically by EVAP-COND 3.0 version simulation package of American National Institute of Standards and Technology. It is found that as the circuit number increases the temperature difference between the air and the refrigerant increases, but it reduces the overall heat transfer coefficient. The evaporator capacity will rise firstly, and then drop with the circuit number and achieve the maximum in the optimum circuit number. Therefore, selecting the appropriate circuit number of the evaporator can significantly improve the efficiency and optimize the design.

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