How Many Types Of Data Center Cooling Systems?

- Feb 05, 2018-

A large number of data centers focus on cooling and humidity control, most concerned about energy consumption, some focus on workload management and performance optimization, and other concerns about data center design and layout. This article focuses on the rich cooling and humidity system control of modern data centers:

Free cooling system

Sealed cooling system

Non-integrated humidification

Dew point humidity control

Evaporation or adiabatic cooling

Higher operating temperature

Tight coupling or heat source cooling

Intelligent interconnection cooling system

Chimney cabinets and ceiling ducts

Most of the above measures focus on saving energy by focusing on operating temperatures, cooling with ambient air and targeted air instead of lowering the entire data center to unnecessary cryogenic temperatures.

Tight coupling or heat source cooling

Tightly coupled cooling achieves more efficient operation by being close to the heat source. It's nothing new - ask the old mainframe operator or any laptop designer. Tightly coupled cooling is still "mainstream" in the data center, but newer approaches tend to do better and get more attention in meeting energy efficiency needs. It works simply by consuming energy to blow large amounts of air into the under-floor space or air ducts and then pulling the air back into the air conditioner.

More promising technologies include immersion cooling: immersing the server in mineral oil as a whole to achieve extremely high cooling rates with minimal energy consumption. However, technical staff need to be full of oil inside and outside the server for processing, the heart will think? Obviously this cooling method is not suitable for all scenarios.

Rear door cooler

The level of acceptance is also very high, in part because of water-cooled way to regain attention. If the huge room air-conditioning system to cancel, switch to close to the new cooling equipment, I believe the data center industry will run better than now. Educational Background and Hope Individual personal differences may create new cases, but the conflict between cost and power availability will determine the end result.

Higher operating temperature

The American Association of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) first published its recommendation for a higher-temperature data center in 2008, but did not notice it. The server does not need to be refrigerated. These units will still perform well even if the inlet air temperature reaches 75 to 80 ° F (25 to 27 ° C). Server manufacturers have actually expanded the operating temperature range of the product, and the old equipment is actually just as capable as the new equipment running in an extended temperature range. Raising the operating temperature can result in significant energy savings, but one must first approve this approach and then agree to make the hot aisle hotter - imagine what the 100 ° F (38 ° C) temperature is? This will stimulate the application and popularity of back door coolers.

Free cooling

Higher operating temperatures also often benefit free cooling systems. In the ASHRAE 90.1-2010 guidance document, free cooling is almost a mandatory energy-saving requirement and will be universally applied. Capital investment in energy conservation will partially offset the benefits of operating cost savings. But achieving free cooling while retrofitting or upgrading is also a technical and investment challenge. It is expected that new standards will emerge in the next two years, making free cooling more feasible. Free cooling near the water may be more advantageous, but we will see more examples of air-cooled Japanese Kyoto Wheel. Eventually, data center operators will be able to adopt free cooling measures at more climatic conditions than previously anticipated, in part because of the higher operating temperature contribution.

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Evaporation or adiabatic cooling

While the scientific principles of evaporative cooling are simple and are gaining in popularity, they are still new to most data center operators. Adiabatic cooling achieves cooling by reducing the pressure on the operation of a substance in a closed environment, boiling them up as magma floats on the surface of the volcano and wind-removing the high temperatures on the mountain. Adiabatic cooling is still effective in warm, dry climates, which greatly broadens the availability of "free cooling" throughout the year. The main drawback is that there is a lot more water used, but with the same amount of cooling it still requires considerably less cooling water than a standard cooling tower.

Sealed cooling

Sealing can not solve the problem of overheating due to incorrect cooling planning, inadequate air flow or cooling capacity. The latest National Fire Protection Association commercial standard (NFPA-75) may make sealed cooling solutions more difficult to achieve. Renovations to sprinkler and / or gas fire extinguishing systems will add significant cost. In addition to trying to avoid mistakes, day-to-day optimization is also important: blinds must be installed in unused racks, holes in raised floors must be closed in time, and drains that affect ventilation below the floor must also be cleaned .

Chimney cabinets and ceiling ducts

Using the air duct formed by the space above the ceiling to transmit the air to the room air-conditioning system to ensure that the return air returns to the air-conditioning cooling coil at the highest temperature can significantly increase the cooling capacity of the precision air-conditioning system. The final form of equipment that combines suspended duct and hot-aisle measures is the chimney cabinet for maximum cooling efficiency. High-temperature exhaust gas from the server cluster is discharged from the stack at the rear of the cabinet and returned to the air-conditioning unit directly through the air duct above the ceiling of the suspended ceiling. The whole process of hot air and cold air to maintain separation, so you can maintain a high energy efficiency ratio.

Although the effect is obvious, the chimney cabinet has not been vigorously promoted or widely accepted. This may be because the hermetically sealed design is more flexible and can use more cabinets for the same effect. However, chimney cabinets allow the entire room to maintain cold-aisle temperatures and make the work environment more comfortable.