Abstract:

Experimental study of electricity defrosting and hot gas defrosting was done based on a low-temperature cold storage existing. The design of partition device was introduced. The effect of humidifying amount on defrosting time, defrosting load, temperature field around the air-cooler when defrosting were discussed at two kinds of situation with partition device or no. The results show that, with the increasing amount of humidification, defrosting energy consumed also increases accordingly, more than 18% when the humidifying capacity is 1000 g. Electricity defrosting was bigger to the damage degree of cold storage temperature field. The cold storage temperature is increased by 5℃ to 10℃. After the partition device was set up, there was a notable energy conservation effect, the temperature field of cold storage was less destroyed. The maximum change of cold storage temperature is decreased by 5℃ with electricity defrosting. The influence of the partition device to hot gas defrosting was relatively smaller.

Key words: heat transfer, partition board, defrosting, phase change, temperature field, humidification

摘要：

针对一套已有的低温冷库,设计了一套冷风机隔断装置,通过对冷风机电热和热气这2种不同融霜方式的实验研究,探讨了有无隔断装置两种情况下,加湿量对融霜时间、融霜负荷及融霜过程中对冷风机周围温度场的影响。结果表明:随着加湿量的增加,融霜所需的能量也相应增加,在加湿量为1000g时,融霜能量增加超过18%。电热融霜对冷库温度场破坏程度较大,融霜结束时,库温升高5~10℃。在增加隔断装置后,能耗显著减少,可达20%左右;也大大降低了对库内温度场的破坏,电热融霜时,库温最大变化量降低5℃,对于热气融霜的影响相对较小。

关键词: 传热, 隔断装置, 融霜, 相变, 温度场, 加湿