Experimental investigation of an integrated cooling system driven by both liquid refrigerant pump and vapor compressor

The energy consumption of air conditioning system accounts for a significant proportion of the total energy consumed in data center. To reduce the energy consumption of the cooling system, an integrated system, which combines pumped refrigerant two-phase cycle (PRTC) with vapor compression cycle (VCC), is proposed in this paper. The impacts of input frequency and outdoor air temperature on the performances of PRTC, and that of the outdoor air temperature on the performances of VCC have been investigated. It was found that PRTC had higher EER than VCC, but its cooling capacity was limited by outdoor air temperature. In PRTC, the designed cooling capacity of 2500 W could be obtained when the outdoor air temperature was −3.0 °C. In addition, 80% and 50% of the designed cooling capacity can be obtained at ambient temperatures 3.2 °C and 12.0 °C, respectively. Besides, the feasibility of the system in different climate zones in China was demonstrated by analysis of the climate data in Harbin, Beijing, Wuhan, Guangzhou and Guiyang, respectively. Results indicated the proposed system had high feasibility in Harbin and Beijing. The results of this paper can provide valuable insights into the cooling system driven by both liquid refrigerant pump (LRP) and vapor compressor, targeting at reducing the cooling energy consumption and maximizing the economic efficiency of the cooling system in data center.