CFD-Based Operational Thermal Efficiency Improvement of a Production Data Center

Effective cooling of data centers presents a dual challenge: increased cooling power to meet the ever increasing device heat loads, and the need for energy efficient cooling. Detailed analysis of the thermal and flow conditions within a data center are necessary for obtaining optimal design and operational parameters. This paper describes the application of a computational fluid dynamics (CFD) based model in a production data center for improving its operational efficiency. The model used in the present work is based on conjugate heat transfer and fluid flow at data center level. The effect of heat dissipation from racks, and thermal and flow conditions at perforated tiles are bought into the model through boundary conditions. The model is rigorously validated by comparing simulation results with actual measurements. Extensive parametric studies have been performed, and key issues, resulting in mixing and ineffective cooling, have been identified. Several design and operational changes have been recommended in terms of placement of blanking panels, operation of CRAC units, and operating set-points. These recommendations have been implemented at the data center, resulting in energy savings to the tune of 20%. Further, the model has been used extensively for obtaining guidelines for efficient ramping up of the data center.