CFD Analysis of Data Center Hall Cooling Performance under Normal and Failure Modes with Control Strategies and Airflow Leakages

Data centers have become the backbone of an increasingly digitized world, supporting the rapid growth of cloud computing, big data, IoT, 5G, and other emerging IT technologies, with rising demand and innovations in AI and ML reinforcing their significance. Data centers are energy intensive, with data processing and storage accounting for 3 to 4% of global energy consumption, which continues to grow annually. Improving their efficiency is therefore a major industrial challenge, offering substantial cost savings. The modern data center involves an intricate interaction between various mechanical, electrical and control systems. The many possible operating configurations and non-linear interdependencies make it challenging to understand and optimize energy efficiency. In the present study, computational fluid dynamics (CFD) analysis is used to assess the cooling performance of a dynamically controlled data center hall with non-raised floor configuration and hot aisle containment (HAC) strategy. The operation of air-cooling units (ACUs) is dynamically regulated in response to the data hall IT load through an integrated network of sensors and controllers. These controllers modulate ACU fan speed and chilled water flow rates to maintain the IT cabinet inlet air temperature within each ACU’s zone of influence and below the specified threshold. This control strategy, informed by real-time temperature and pressure sensor data, ensures desired thermal conditions within the data hall while optimizing overall cooling power consumption. This study focuses on two modes of operation for the purpose of design analysis, i.e., normal mode (NM) and failure mode (FM). Based on CFD simulation results, the present paper highlights the effects of control strategy used for ACUs, cooling airflow leakage, recirculation of hot air on the performance of the data hall cooling design. Different simulation scenarios, which accommodate all possible combinations during NM and FM of operation i.e., with & without control and with & without leakages are evaluated to understand the significance of various design parameters, leading towards the right design. Results show that the control strategy delivers approximately 9.89% energy savings in normal mode, while leakages significantly degrade performance during failure mode.