Ramification of Server Airflow
Leakage in Data Centers with
Aisle Containment
Daniel Kennedy
January 6, 2012
Cold and hot aisle containment has become a widely accepted method of increasing the
efficiency of data center operation. The concept of physically separating cold and hot air
paths in the data center makes logical sense, and on the surface aisle containment provides
a simple method to remove the chance of any airflow mixing. However, like most data center
operation concepts, the true nature of containment is more complex. Uneven pressure distribution between cold or hot aisles, as well as uneven loading, both static and dynamic can
dramatically reduce the ability for aisle containment to successfully achieve the ideal efficiencies that are often the key driver for aisle containment deployment.
This paper will explore the application of aisle containment, and the reality of server airflow
leakage that results in bypass air that is at the heart of this inefficiency. The paper will then
explore methods of eliminating this bypass air, and bringing aisle containment in-line with the
theoretical models used in the marketplace.
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