摘要
针对大中型空气源热泵系统除霜,提出一种空气源热泵蒸发器并联轮换除霜系统,该系统能够实现除霜时不停止制热。为分析系统的结霜/除霜特性,建立空气源热泵蒸发器并联轮换除霜系统理论模型。通过模拟研究蒸发器并联轮换除霜系统结霜/除霜过程中霜层和系统制热性能随运行时间的变化情况。结果表明,在环境温度-5℃,相对湿度80%时,系统运行60 min时,室外机霜层厚度已影响机组正常运行;在运行40 min时开始运行除霜,除霜周期为15.76 min,获得的最大制热量为7.94 kW,最大制热COP为2.77。
In view of defrosting of large and medium air source heat pump system,a defrosting in turn of air source heat pump system with evaporators in parallel is proposed.The system can realize defrosting without stopping heating.In order to find out the frosting/defrosting characteristics of the system,the theoretical calculation model of the system is established.Through numerical simulation,the variation of frost layer and system heating performance with operation time in the frosting/defrosting process is studied.The results show that under the condition that the ambient air temperature is-5℃and the air relative humidity is 80%,the thickness of frost layer accumulated on outdoor unit has affected the normal operation when the system operates heating mode for 60 minutes.If the system begins to convert into defrosting mode when it operates heating mode for 40 minutes,the defrosting cycle is 15.76 minutes,the maximum heating capacity is 7.94 kW and the maximum heating COP is 2.77.
作者
牛建会
马国远
范秀颂
许树学
Niu Jianhui;Ma Guoyuan;Fan Xiusong;Xu Shuxuen(Beijing University of Technology;Hebei University of Architecture)
出处
《制冷与空调》
2020年第2期15-20,共6页
Refrigeration and Air-Conditioning
关键词
空气源热泵
蒸发器并联
除霜
理论模拟
air source heat pump
evaporators in parallel
defrosting
theoretical simulation
