冷热水三联供空调机组的除霜特性

三联供机组在冬季运行时，由于室外换热器表面结霜会严重影响机组的运行性能和安全系数。本文针对三联供空调机组所采用的除霜策略进行实验，研究了不同化霜温度测点对机组除霜特性的影响。结果表明：当化霜温度传感器置于室外换热器表面的测点2和测点5时，系统在结霜过程中持续波动的时间分别为2280ｓ和220ｓ；除霜时间分别为5min和12min,系统过热度持续为负值的时间分别为185ｓ 和80ｓ。为系统安全考虑，建议化霜温度传感器布置于测点5。

Defrosting Characteristics of Refrigeration, Heating, and Hot Water Combined Air-conditioning System

Frost on the surface of an outdoor heat exchanger will seriously affect the operating performance and safety factor of a refrigeration-, heating-, and hot-water combined air-conditioning system when it is operating in winter. According to the defrosting strategy of the system, the influence of different defrosting temperature sensor positions on the defrosting characteristics of the unit is explored by carrying out experimental research. The results show that when the position of the defrosting temperature sensor is located at measuring point 2 and measuring point 5 on the surface of the outdoor heat exchanger, the duration of the system fluctuation during the frosting process is 2280 s and 220 s, respectively. The defrosting time was 5 min and 12 min, respectively, when the defrosting temperature sensor was located at measuring point 2 and measuring point 5. In addition, the time during which the superheat degree of the system continued to be negative in this process was 185 s and 80 s, respectively. Considering the safety of the system, it is recommended that the defrosting temperature sensor be placed at measuring point 5.