Study of Circuit Number on the Evaporator in CO2 Heat Pump Water Heater
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.
Dongye Sun, Wen-Pei Sung and Ran Chen
K. Liu et al., "Study of Circuit Number on the Evaporator in CO2 Heat Pump Water Heater", Applied Mechanics and Materials, Vols. 71-78, pp. 2266-2270, 2011