With the increase in the heat flux density of data centers, liquid cooling of data centers is becoming increasingly important. A cooling tower is typically employed in liquid cooling systems and its cooling performance is affected by ambient temperature and relative humidity. In this study, we analyze the effects of these factors on cooling performance as well as power consumption, which have previously not been studied in detail. For this purpose, we built a 4.8 kW data server cold-water system and used a fin-type water-cooled radiator for heat dissipation. The energy consumption of the cooling system under different ambient temperature and relative humidity conditions was simulated and analyzed using TRNSYS simulation software. Assuming that the chip operating temperature is 70 °C, when the ambient temperature increases from 5 °C to 30 °C, and the ambient relative humidity increases from 40 % to 80 %, the optimal primary cooling water flow and the secondary cooling water flow increase accordingly, and the corresponding energy consumption of the cooling system increases. By considering the optimal flow rates, we found that the power usage effectiveness (PUE) is in the range 1.14–1.21.
Keywords data center, power consumption, cooling tower, ambient temperature, relatively humidity