Wednesday, March 25, 2015

Data Center Design Consideration: Cooling

Further to the previous articles in Data Center Design Consideration: Space Planning, thermal management is also an important consideration in data center design. As more cloud-based platform and applications developed and the big data trends, the demand for server usage and data storage will grow continuously. As a result, more power is consumed and more heat is generated by the servers and electronics. Proper heat dissipation techniques are therefore necessary to ensure heat is effectively removed from the equipment.




Proper design for data center cooling at least has 3 components:


Mechanical, Ventilation and Air-conditioning (MVAC) Precision System

It supplies and distributes chilled air into the computer room. The MVAC system is designed based on the total heat load of the equipment. Depending on the geographical location of your data center, temperature is typically kept between 20 - 25 degree.





Rack Layout

The TIA-942 standard recommends the use of a hot aisle and cold aisle layout in positioning racks. Racks are organised in rows with an aisle dividing each row of racks. Racks are then installed with either the front or the rear of the rack facing each other along every aisle.




The aisles, which access the front, are designated cold aisles while the aisles that access the rear are designated hot aisles.

With this layout, cooled (fresh) air is introduced into the cold aisles. As the cooled air enters the rack and moves from the front to the rear, it extracts heat from the rack-mounted equipment. At the rear, air is expelled into the hot aisles where they are directed back to the Air Handling Units (AHU) / Computer Room Air-conditioning (CRAC) Units. Using this directed path of air circulation, the computer / servers equipment are effectively cooled.



Source: http://macc.umich.edu


Rack Design

In order to make the cool aisle / hot aisle layout effective, the rack are required to be carefully installed and designed. It ensures cooled air enters the rack, is forced through the equipment and hot air is expelled from the rack:

  1. Intelligent fan doors for drawing cooled air into the rack.
  2. Blower fans to ensures cooled air is available along the front of the entire rack.
  3. Fan doors and blower fans are used when there are insufficient air entering the cabinet.
  4. Filler panels and air dams for blocking gaps between the front and rear of the rack.
  5. Air diverter kits to divert cooled air upwards which helps air to flow into the equipment and to prevent hot air at the back from re-circulating to the front.



About SMA

Strategic Media Asia (SMA), a critical infrastructure training and event organizer based in Hong Kong, provides an interactive environment and opportunities for members of IDC industry and engineers to exchange professional views and experience on critical infrastructure and E&M facilities.

SMA is one of the CPD Course Providers of the Chartered Institution of Building Services Engineers (CIBSE).

For details of other data center courses and seminars, please visit our website at http://www.stmedia-asia.com/trainings.html.