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Fundamentals of Data Center Airflow Management

  • Pramod Kumar
  • Yogendra Joshi
Chapter

Abstract

Airflow management is probably the most important aspect of data center thermal management. It is an intricate and challenging process, influenced by many factors. This chapter presents some of the fundamental concepts governing airflows in today’s data centers. As such, it provides a foundation necessary for understanding the remaining topics discussed in the book. The chapter begins by introducing the concept of system pressure drop and its influence on the computer room air conditioning (CRAC) unit performance. Various factors contributing to the overall pressure drop, such as plenum design, perforated tile open area, and aisle layouts, are described. Some of the key aspects of room and rack airflows are also discussed. The second part of the chapter highlights the importance of temperature and humidity control in data centers. The basic concepts of psychrometrics are introduced. Specific examples on data center cooling processes, such as sensible cooling, humidification/dehumidification and evaporative cooling are illustrated with the help of the psychrometric chart. The concept of airside and waterside economizers for data center cooling are introduced. The third and final part of the chapter describes an ensemble COP model, for assessing the overall thermal efficiency and performance of the data center.

Keywords

Data Center Humidity Ratio Plenum Pressure Static Pressure Rise Psychrometric Chart 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.G.W. Woodruff School of Mechanical EngineeringGeorgia Institute of TechnologyAtlantaUSA

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