采用电子膨胀阀和毛细管的空气源热泵热水器性能对比实验研究
Comparative experimental study on performance of air-source heat pump water heaters with electronic expansion valves and capillary
摘要：
为研究不同节流方式对空气源热泵热水器性能的影响,分别以毛细管(CAP)和电子膨胀阀(EEV)作为节流元件研制了样机,通过实验对比研究其运行特征。结果表明:CAP系统的吸气过热度能稳定在1 ℃左右;CAP系统的排气温度相对更低,约比EEV系统低15 ℃;加热同样一箱水,CAP系统的制热速度更快;EEV系统的COP和全年性能系数(APF)均高于CAP系统,但在名义工况下CAP系统具有与EEV系统相当的制热COP。综合考虑制热性能及初投资等因素,可根据需要优先采用毛细管作为节流装置。
Abstract：
In order to study the impact of different throttling methods on air-source heat pump water heaters, a prototype is developed by using capillary (CAP) and electronic expansion valves (EEV) as throttling components, respectively, and their operating characteristics are compared through experiments. The results show that the inspiratory superheat of CAP system can be stabilized at about 1 ℃. The exhaust temperature of the CAP system is relatively lower, about 15 ℃ lower than that of the EEV system. The heating speed of the CAP system for heating the same tank of water is faster. The COP and the annual performance factor (APF) of the EEV system are higher than those of the CAP system, but under the nominal operating conditions, the CAP system has a comparable heating COP to the EEV system. Considering the factors such as heating performance and initial investment, capillary can be preferred as throttling devices according to needs.
Keywords:air-source heat pump water heater; electronic expansion valve; capillary; throttling; annual performance factor (APF); coefficient of performance(COP); experimental study