Why improving Data Centre rack airflow is important

Data Centre rack airflow management is the second step within the 4Rs of Airflow Management and is key to helping optimise cooling, improve energy efficiency and reducing costs.

As June is Airflow Management Awareness Month, we are looking at the steps that can be taken at Raised Floor, Rack & Row levels that help enable changes to be made to CRAC units at the Room level, that help optimise cooling and lead to energy reductions. In our last blog, ‘Improving Raised Floor Airflow Management Helps Optimise Data Centre Cooling’, we looked at the changes needed to be made at the first level – Raised Floor.

The next step is to improve airflow management at Rack level. Data Centre racks contain the IT equipment that is critical to business continuity. Ensuring this equipment is cooled correctly is vital to its performance and longevity. As discussed in our last blog, the key to improving airflow management is preventing the mixing of cold air streams used to cool the equipment and the hot exhaust air stream ejected by the equipment.

Within data centre racks, airflow issues can arise through hot exhaust air circulating from the back of the rack to the front. Here it can pass through gaps and mix with cold air cooling the equipment. This can cause hotspots and can affect the cooling capacity, as hot exhaust air can be drawn into the equipment’s air intakes. This can lead to performance issues, and in severe cases reduce equipment lifetimes or cause equipment to shut down. Areas within the rack where this can occur can be found in the unused space between installed equipment, along with gaps found between the mounting frame and the sides of the rack (including between the tops and bottom).

Unused rack space can be sealed off through the use of blanking panels. Our recent blog, ‘Blanking panels from EDP won’t break the bank to stick in a blank’, covered the use of blanking panels and the important role they play in improving rack airflow management. In this article we will cover the importance of sealing the other gaps.

Whilst the importance of using blanking panels has started to be recognised by the Data Centre industry as a way to improve airflow management, and help comply to the best practices laid out in the European Code of Conduct, few are completely sealing the face of their Data Centre racks. Hot air is still able to re-circulate to the front of the rack and mix with the cold air through the gaps between the mounting frame and the side of the rack or between the mounting frame and the top and bottom of the rack.

Even if blanking panels are being used, hot exhaust air can still affect performance. By removing this issue, it is still possible to further improve airflow management and optimise cooling to a higher level.

Some rack manufacturers have recognised this issue and now install brush strips to their mounting frames. These reduce the amount of hot exhaust air circulating to the front of the rack whilst still allowing cables to pass through. But, what about existing racks? What can be done to solve this issue?

Data Centre Rack Airflow Management Solutions

EDP Europe is recognised as a leading provider of airflow management solutions that help optimise cooling. At rack level this can be achieved through the use of EziBlank, HotLok or PlenaFill blanking panels for sealing unused rack space. For gaps around the mounting frame EDP Europe offers two solutions:

1. RackSEAL

RackSEAL is a compressed foam tape air barrier that has an adhesive acrylic scrim that enables it to be easily applied to the mounting frame or sides of the rack. Once applied RackSEAL will expand and provides an effective seal. RackSEAL will mould around any obstructions such as cables, and is available in two compressed widths.

2. HotLok Rack Airflow Management (RAM) Kit

The HotLok RAM Kit has been purposely designed by Upsite Technologies to seal the gaps between rack mounting rails and the sides of the rack enclosure. HotLok RAM kit comprises of either a 45° or a 90° profile that attaches to the side rails of the mounting frame. There’s then a choice of three widths of membranes that fit into the profile and seal against the rack sides.

Both of these solutions results in a similar outcome.

By sealing all the gaps within the rack face of a data centre rack it prevents hot exhaust air from circulating back to the front of the rack and mixing with the cold air cooling the equipment. This reduces the risk of hotspots and can help enable the raising of CRAC unit set-points which leads to energy efficiency gains.

If you would like more information on data centre rack airflow management, or have issues optimising cooling that you would like assistance with, please contact us and a member of our team will be happy to help.