分流器和集管对液体冷媒除霜系统的影响研究

Study on the Influence of the Distributor and Header on the Liquid Refrigerant Defrost System

液体冷媒除霜系统具有在除霜期间制冷过程连续,库温波动小,无需附加能耗的优势。为了探究分流器和集管对液体冷媒除霜系统性能的影响,在库温为-5℃和-15℃的工况下,分别采用分流器和集管供液的方式进行试验。对比分析库温的变化,除霜速率和蒸发器进出口温度压力的变化。结果发现:在-5℃的工况下,采用分流器的除霜时间为820s,集管为710s;采用分流器的库温最大升高值为5.5℃,集管为4℃。分流器的节流作用降低了进入蒸发器制冷剂的温度,造成除霜期间库温升高幅度增大,延长除霜时间。因此,对于液体冷媒除霜系统采用集管式分液方法更为合理。

The liquid refrigerant defrost system has many advantages:the refrigeration process is continuous during the defrost period;the temperature fluctuation of the cold storage is small;and there is no additional energy consumption.In order to investigate the influence of the distributor and header on the liquid refrigerant defrost system,the distributor and header were used for experiment under the working condition of-5℃and-15℃.The cold storage temperature change,the defrost rate,the inlet and outlet temperature and pressure of the evaporator were compared and analysed.The results showed that the defrost time of the distributor was 820s,and the header was 710s under the temperature of-5℃.The maximum temperature rise value of the distributor was 5.5℃,and the header was 4℃.The temperature of the refrigerant into the evaporator was reduced,the cold storage temperature rise was increased,and the defrost time was prolonged by the throttling effect of the distributor during the defrosting.Therefore,it is more reasonable for the liquid refrigerant defrost system to adopt the method of the header.