Case Studies

Rugged Blade Server Enclosure

In the commercial world, Internet data centres are the most competitive and processing-hungry places on the planet. The processing is carried out by blade server ‘farms’, and processing demand in these centres is so intense that it needs to be spread across several blades. The software technology that facilitates this is called virtualization. Virtualization software sits at the core of the processing, providing a virtual PC interface to each application. This allows many applications to run on one blade and, more importantly, the hardware becomes independent of the application.

Applied to naval mission systems, virtualization provides a processing ‘cloud’ on which all the various applications – sonar, combat management, EW etc – can run side by side, irrespective of operating system and network interfaces. Blade servers perform the processing in a virtual computing environment, taking in information from the vessel’s sensors via interface electronics. This has benefits in reducing cost and providing an open systems architecture that simplifies obsolescence management and system upgrades.


The size and component density (and subsequent heat output) of blades mean, however, that they can be inherently less robust than other industrial electronics form factors, so care is needed in their selection and ruggedisation for military use.


When investigating the feasibility of introducing virtualization into the naval domain, BAE Systems recognized the depth of experience and knowledge vested in the Aish Technologies design team and asked them to come up with a means of ensuring that the blade servers would survive a naval environment.


Their answer was a rugged blade server cabinet (pictured) that houses sixteen blades in a compact, environmentally-controlled cabinet. The cabinet, known as the Shared Computing Environment (SCE) enclosure, is constructed using Aish’s proven High Stress II build system of aluminium frame members and steel corner brackets, which produces a light, strong and rigid enclosure that is versatile in its internal configuration and external dimensions. The blades are fitted into the enclosure within their own dedicated COTS chassis so that essential services are maintained. Peripheral components such as network switches etc can also be housed within the enclosure.

Cooling is facilitated by chilled water: an internal air circuit is forced through the servers by centrifugal fans; the heated air is directed through the heat exchanger and re-circulated within the sealed Aish enclosure in a closed system that keeps the COTS electronics from expelling toxic fumes in the event of a fire. The heat exchanger is an Aish design that is much cheaper than the third party products traditionally specified, helping to keep processing cost as low as possible.

The initial application, for the RN’s Astute Class submarines, was such a success that variants of the Aish SCE Enclosure have been developed for the introduction of virtualization into further RN classes. These variants include cabinets designed for platforms where chilled water is not available and cooling is achieved with blown air.

The SCE family of enclosures demonstrates that Aish Technologies’ designs can overcome the most arduous of conditions to provide cost effective solutions whatever your needs.