数据中心空调机组风机运行模式的数值模拟研究

Numerical Simulation Research on Fan Operation Mode of Computer Room Air Conditioners in Data Centers

不少数据中心机房的空调机组使用回风温度控制,在回风温度低于设定温度时压缩机停机、风机保持运转,这使得地板下送风存在明显的冷热混合现象,带来效率损失。为避免该现象,以某数据中心机房为研究对象,通过CFD模拟分析了压缩机停机+风机停机时的气流组织,与压缩机停机+风机运转时的情形进行了对比。结果表明:对于空调机组中少数不相邻的空调,当压缩机停机+风机停机时,静压箱内气流仍然能保持良好的均匀性,不会导致靠近停机空调的机柜进风温度明显高于其他机柜;当压缩机停机+风机运转时,高温气流送至静压箱内会严重破坏气流组织的均匀性,靠近停机空调的机柜平均进风温度明显升高,热环境恶化。因此,压缩机停机时风机最好停机,并采取其他措施给机房空调提供开机信号。

Computer room air conditioning units in lots of data centers operate depending on the return air temperature.When the return air temperature is lower than the set temperature,the compressor stops running and the fan keeps running.As a result,the hot air is sent to the floor plenum and mixes with the cooled air,causing reduction of cooling efficiency.In order to avoid this phenomenon,a typical data center room is taken as the research object,and the CFD tool is used to model it.Two operation schemes of stop are simulated,one in which both the compressor and the fan stop running,and the other in which the compressor stops running and the fan keeps running.The airflow organization under the two schemes is simulated and compared.For few non-adjacent computer room air conditioning units,when both the compressor and the fan stop are running,the air in the floor plenum remains uniform.At the same time,the inlet air temperature of the cabinet near the non-operating air conditioning unit is close to those of other cabinets.When the compressor stops running and the fan keeps running,the hot air seriously destroys the uniformity of the airflow organization in the floor plenum.At the same time,the average inlet air temperature of the cabinet near the non-operating air conditioning unit increases significantly,and the thermal environment deteriorates.Therefore,the fan had better stop running when the compressor stops running.Other measures need to be taken to provide the boot signal for the air conditioning units.