双级耦合热泵供暖化霜

在江浙等湿热地区应用双级耦合热泵即空气源热泵代替水环热泵系统中的锅炉，空气源热泵制取低温热水作为水环热泵的热源，空气源热泵制冷循环除霜会使其供热量减少.在水环热泵空调系统中有串联在水环路上的蓄热水箱来改善系统的运行特性.通过计算，选择了合适的空气源热泵、水环热泵和蓄热水箱，通过实验研究了蓄热水箱对化霜的影响.由于蓄热水箱的存在，中间环路的热惯性较大，空气源热泵机组结、化霜对系统的影响与室温的稳定性几乎无关.空气源热泵机组可以应用于该系统，本实验系统的各项技术指标均能满足实际工程要求，为推广应用提供了必要的数据.

Defrosting in double stage coupling heat pump heating system

A double stage coupling heat pump composed of the air source heat pump instead of the boiler and the water loop heat pump was proposed for the cold and wet zone like Jiangsu and Zhejiang Province. Low temperature water from the air source heat pump was supplied to the water loop heat pump unit. Heating capacity decreased during defrosting by the air source heat pump. A heat storage tank was connected in series with the water loop to improve the system running characteristics. The air source heat pump, the water loop heat pump and the heat storage tank were selected through calculation. The effect of the heat storage tank on defrosting by the air source heat pump was tested. Due to the existence of the heat storage tank, thermal inertia of the loop was relatively high. The frosting and defrosting courses of the air source heat pump had little effect on the room temperature. The air source heat pump can be used to run the system. All of the system indices met practical demands, providing necessary test data for promotion and application of the system.