The role of data centers in modern life has expanded rapidly over the past decades. In addition, this expansion has resulted in a significant increase in the share of data centers in total energy consumption of the world. Thus, reliability and energy efficiency have become a common concern in data centers. Information technology equipment (ITE) and cooling infrastructure are the largest power consumer in data centers. The cooling power in a data center depends on the amount of heat dissipated by ITE. Therefore, the thermal design of the ITE impacts not only the ITE power but also affects the infrastructure power and has a significant role in the overall efficiency of data centers. This paper studies the impact of fans location and airflow balancing on the thermal performance and power of a server. A detailed computational fluid dynamic (CFD) model of the server is built, calibrated and validated using experimental test results. Next, impacts of moving fans to the rear side of the chassis on the flow rate and temperature of components are investigated. Special attention is given to controlling airflow through power supplies.
This content will become publicly available on September 1, 2023
Experimental and Numerical Analysis of Data Center Pressure and Flow Fields Induced by Backward and Forward CRAH Technology
Abstract An increasingly common power saving practice in data center thermal management is to swap out air cooling unit blower fans with electronically commutated plug fans, Although, both are centrifugal blowers. The blade design changes: forward versus backward curved with peak static efficiencies of 60% and 75%, respectively, which results in operation power savings. The side effects of which are not fully understood. Therefore, it has become necessary to develop an overall understanding of backward curved blowers and compare the resulting flow, pressure, and temperature fields with forwarding curved ones in which the induced fields are characterized, compared, and visualized in a reference data center which may aid data center planning and operation when making the decisions of which computer room air handler (CRAH) technology to be used. In this study, experimental and numerical characterization of backward curved blowers is introduced. Then, a physics-based computational fluid dynamics model is built using the 6sigmaroom tool to predict/simulate the measured fields. Five different scenarios were applied at the room level for the experimental characterization of the cooling units and another two scenarios were applied for comparison and illustration of the interaction between different CRAH technologies. Four scenarios were used to characterize a more »
- Award ID(s):
- 1738793
- Publication Date:
- NSF-PAR ID:
- 10338808
- Journal Name:
- Journal of Electronic Packaging
- Volume:
- 144
- Issue:
- 3
- ISSN:
- 1043-7398
- Sponsoring Org:
- National Science Foundation
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