Hot, Cold…or Up. What’s the Best Method of Containment?
March 19, 2020
For years, there’s been a relatively popular, prevailing thought that cold aisle containment (CAC) is the most efficient cooling method in the data center. But do we know exactly why?
Is cold aisle cooling really “the best” method of containment?
The most common response is because in cold aisle containment, the chilled air that exits a raised floor technically only has to travel a short distance up to the server cabinets its meant to cool. Short and sweet, right? Not so fast.
The challenge in this CAC scenario is that the once-chilled air still has a full and complete circulation path that it must travel from the cooling unit to the device and then back to the cooling unit. After it’s all said and done in one complete loop, the savings all but vanish.
Don't forget, too, that even with cold air being dispensed closer to the device, the assumption that this shorter distance reduces the potential for air to mix and become hotter is simply not true. Once air is allowed to mix, the savings and value continue to diminish.
So, can installing containment reduce mixing of air?
Maybe. The first step of isolation really starts sooner, at the cabinet level. Think of it like the low-hanging fruit that you can tackle first. Watch this video to get a better understanding:
Device-level containment, too? Tell me more.
One of the key points to air containment is to seal the openings in and around compute devices. This includes the openings above and below the device as well as along the sides, top and bottom. Air will seek the path of least resistance, and since warm air is lighter and less dense, it’s easily pulled into the intakes of the devices.
With this understanding in mind, it gets much easier to realize why cabinet and device-level containment is critical step to address before any sort of room or space containment is deployed.
Simply put, if you have hot spots or cooling issues, first focus on the low-hanging fruit or cabinet-level containment before spending the time to contain cabinet rows.
Posted by Steven Bornfield, Sr. Technology Consultant at 3/19/2020 5:57:33 AM