Introduction
If you’re deploying the latest generation of information technology (IT) equipment or adding more servers to a crowded data center, conventional data center cooling methods and systems will likely be inadequate. The most effective cooling solution for any computing facility depends on the specific characteristics of the facility, equipment layout, and server density.
This technology brief first explains limitations of traditional cooling practices. Then it describes a range of systems you can choose from to modify or supplement your existing cooling system to get the cooling capacity your data center requires.
Limits of traditional cooling practices
Enterprise data centers have most often used an open-area approach to cool racks of servers and storage systems. With this approach, one or more computer room air handlers (CRAHs) are placed on the periphery of the data center room. IT equipment (ITE) racks are arranged in a cold-aisle/hot- aisle layout (Figure 1). Cool air is forced through a raised floor plenum and up through vented floor tiles in the cold aisle toward the front of the ITE racks. The cool air is drawn through the ITE racks, and warm air is vented out the rear of the racks and upward toward the ceiling. Air circulation works on the basic strategy of providing cool air at the floor level and collecting warm air near the ceiling.
Figure 1: Traditional open-area data center cooling
Basic room requirement: Raised floor
The open-area strategy is generally adequate for racks using up to 10 kilowatts of power and lets data centers scale relatively easily. However, some of the warm air mixes with the cool air, reducing cooling system efficiency. Some equipment generates excessive heat, creating hot spots that need supplemental cooling or specific air channeling. The typical remedy has been to set the cooling system to run colder to compensate for the hot spot.
2
