Stability analysis of reverse cycle defrosting system of air-cooled evaporator

In air source heat pump system, air-cooled evaporator is a key component, and its performance directly affects the operating efficiency and stability of the whole system. Especially in low temperature environment, the surface of evaporator is easy to frost, which not only reduces the heat exchange efficiency, but also may cause the system to fail to operate normally. Therefore, reverse cycle defrosting technology has been widely used in air source heat pump system as an effective defrosting method.
System stability analysis
Temperature control stability: During the reverse cycle defrosting process, the system accurately controls the reversing of the four-way valve and the flow rate of the refrigerant to ensure that the outdoor heat exchanger can heat up quickly and evenly during defrosting, effectively avoiding local overheating or incomplete defrosting. At the same time, the fan of the indoor unit stops running during defrosting to reduce the loss of indoor heat and keep the indoor temperature relatively stable.
Refrigerant cycle stability: Reverse cycle defrosting requires the refrigerant to circulate smoothly in the system to avoid refrigerant retention or leakage during the reversing process. Modern air source heat pump systems are usually equipped with advanced control systems and sensors that can monitor the pressure, temperature and flow of the refrigerant in real time to ensure the smooth progress of the defrosting process.
System structure stability: The reverse cycle defrosting system has certain requirements for the structural design of the outdoor heat exchanger and the indoor heat exchanger. The outdoor heat exchanger needs to have high heat conduction efficiency and good corrosion resistance to cope with high temperature and humidity changes during the defrosting process. The indoor heat exchanger needs to ensure that it can effectively absorb indoor heat during the defrosting period while reducing noise and vibration.
Environmental adaptability: The stability of the reverse cycle defrosting system under different environmental conditions is also one of its important considerations. In extremely low temperature or high humidity environments, the system needs to be able to respond quickly and effectively defrost to ensure the continuous operation of the heat pump system. In addition, the system should also have an intelligent defrosting function that can automatically adjust the defrosting cycle and duration according to the outdoor temperature and humidity conditions to avoid unnecessary energy waste.