Performance optimization and energy analysis of a proposed data center dual-mode air source cooling system on the mode change temperature

This study proposes the use of a novel ambient air mixing control strategy to increase the mode change temperature (MCT) and extend the free cooling operation period of a hybrid air-source data center cooling system. The study experimentally assesses the energy performance of the proposed system, and performs a comparative simulation with a conventional hybrid air-source data center cooling system using EnergyPlus. Outdoor air temperature and intake air volume were used as variables for the simulation according to the climatic conditions of Chuncheon City, South Korea. Results from the study show that the MCT of the proposed system increased significantly with decreasing outdoor air temperature and increasing intake air volume. Whereas the MCT of the conventional system remained constant at 8.6 °C, that of the proposed system increased from 9.5 °C to 12.5 °C as OD air temperature decreased from 24 °C to 15 °C and OD air volume intake increased from 5 % to 30 %. This extended the free cooling period of the proposed system, leading to an annual energy savings of 37 % compared to the conventional system. This demonstrates the great potential of the air mixing control strategy in enhancing the energy efficiency of data center cooling systems.