EXPERIMENTAL INVESTIGATION ON DYNAMIC DEFROSTING CHARACTERISTICS OF AN AIR SOURCE HEAT PUMP
The defrosting characteristics of an air source heat pump (ASHP) adopting four-way valve inversion circulation were experimentally investigated. The circulation parameters, heat capacity, input power of the ASHP unit and the wall temperature of the evaporator under different outdoor conditions and face velocities of the outdoor heat exchanger were measured. The outdoor air temperature was controlled to be from -15 to 5℃, and the relative humidity from 55％ to 90％. The effects of the outdoor environmental parameters and face velocities of the evaporator on the defrosting characteristics were analyzed. The experimental results indicate that the frost accumulation mass is maximum when the outdoor temperature is about 0℃, however the defrosting time and defrosting loss decrease as the outdoor temperature increases. The frost accumulation mass increases as the relative humidity under fixed outdoor dry-bulb temperature increases, but the defrosting time decreases. Meanwhile, it is also found that the defrosting time and defrosting loss are minimum when the face velocity of the evaporator is 1.3 m/s for the tested ASHP unit.
Air source heat pump Defrosting experiment Dynamic characteristics Defrosting loss
Xiangcheng TAO Xianmin GUO Yiguang CHEN
School of Mechanical engineering, Tianjin University of Commerce, Tianjin, 300134, China
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）