Rack-based coolings


Rack-based cooling

Conventional room air conditioning systems are only usable up to a certain power density, mostly up to 10 kW per rack. For higher performances up to approx. 15-20 kW per rack an In Row air conditioning in connection with a cold aisle compartmentalization is an efficient air conditioning solution. Thermally highly loaded racks up to 40 kW can only be protected reliably from overheating with rack based cooling.

This means that racks have to be sealed. Hence this technology is also used with IT safes. The air conditioning unit is either built into the bottom of the rack, into a narrow slide-in beside the rack or between the rack or two racks as it can cool two neighbouring safes at the same time. With sideways arranged cooling every unit of the rack is provided with cool air equally.

The warm waste air of the rack is absorbed at the back of the device and fresh cold air is provided at the front side. This method is very energy efficient, because cold air is provided directly at the heat source, the servers. In addition the efficiency can be increased by separating warm and cold air using deflecting plates.

Since the racks have to be closed, they also need own extinguishing systems, fire detection and a monitoring system. This means high investment costs per rack, but such high efficiency racks usually have a considerably higher server power.

Modern rack based cooling systems have drive regulated ventilators which can adapt their performance to the requirements and only using as little power as necessary. Safety can be increased using an additional redundant system.

As a cooling medium either water or cryogen, or dual systems are possible combining the two. With the use of cryogen the cooling is carried out via compressor. If water is used as cooling medium, there are many possibilities for cooling.

Here also the standard method of cooling is mechanical by means of a compressor. Compressors use relatively high electricity.

However, there are also some other environmentally friendly methods of water cooling, such as geothermic cooling, well water, solar cold, adsorption cold and adiabatic line cooling.

In addition cold outdoor air can also be used for cooling, which is already implementable with water cooling, for the cryogen cooling however, it is only at a developmental stage. Using innovative technology in areas of air conditioning great progress can be obtained reagarding electricity consumption and environmental sustainability. We’ll take care of IT.


print article      share article