过冷度对液体冷媒除霜的影响

Effect of subcooling on the liquid refrigerant defrosting

在结霜质量为3kg的条件下,分别测量了库温为-5℃、-15℃和-20℃时液体冷媒除霜系统的过冷度的变化曲线;并且理论计算了有无过冷度时,系统制冷量的变化。实验表明,制冷剂得到过冷度最大的时刻是除霜开始,最小是除霜结束。过冷度带来的系统制冷量的增加,随蒸发温度的降低而增大。理论计算表明,当库温为-20℃时制冷量增加了43%,库温为0℃时制冷量增加了30%。因此,虽然除霜过程蒸发面积减半,制冷系统仍能输出较大的制冷量,减小库温波动。

Under the condition of the frosting mass of 3 kg,the change curve of the subcooling of the liquid refrigerant defrosting system was measured at the temperature of-5℃,-15℃ and-20℃.And the change of the cooling capacity of the system with and without subcooling was calculated in theory.The experiment shows that the maximum subcooling time of the refrigerant is the defrosting start and the minimum defrosting end.The cooling capacity of the system increases with the decrease of the evaporation temperature.The theoretical calculation shows that when the cold storage temperature is-20℃,the cooling capacity increases by 43%,the cooling capacity increases by 30% when the cold storage temperature is 0℃.Therefore,although the defrosting process of evaporation area is reduced by half,the refrigeration system can output large refrigeration capacity,reduce the temperature fluctuation.