Feasibility study on double-evaporator air-source heat pump systems for alternate defrosting with liquid refrigerant

Proposes an improved air-source heat pump system with alternate defrosting double evaporators using supercooled heat of liquid refrigerant. The basic principle is that the two sets of evaporators are operated in sequence and frosted, and one evaporator in the defrosting state is defrosted using the heat mixed by the condenser outlet high temperature and high pressure refrigerant liquid and the bypass compressor exhaust gas. The other evaporator operates as original to ensure the system maintaining a stable heating operation. Presents the operation process of the system defrost mode. Carries out theoretical calculation and analysis on the feasibility of the refrigerant of supercooled heat defrosting method. Analyses the influence of different environmental parameters on the defrosting time. Compares the performance of the system with that of the reverse cycle defrosting system.