Performance study of booster-driven hybrid cooling units for free cooling in data centers

Abstract

The booster-driven hybrid cooling unit using ambient energy for free cooling can work for a whole year as one unit and reduce the annual cooling energy consumption effectively in data centers. Two different type booster and its hybrid cooling units were developed and tested. The suction/discharge pressure and mass flow rate of two different boosters were studied under the annual temperature difference range. The performance and differences of two hybrid cooling units were analyzed. The results indicate that the suction/discharge pressure ratio of the large torque booster (No.1) is less than that of the small torque booster (No.2). In the test temperature difference range, the suction/discharge pressure ratio of No.1 booster decreases by 53.56%, which of No.2 booster decreases by 32.89%. The cooling capacity and energy efficiency ratio of No.1 booster-driven hybrid cooling unit (14.8 kW) is higher than that of No.2 booster unit (9.2 kW) at the same temperature difference (30 ℃).

Keywords

• data center
• booster
• free cooling
• hybrid unit
• pressure ratio