Alan Vincent – Sales Director – Foremost Electronics
How do you maintain maximum IT availability while minimizing operational costs and energy consumption? This is the main question that most concerns the community of plant planners, thermal engineers, architects and others responsible for the implementation of powerful IT equipment.
Dense clusters of high-performance connected equipment no longer allow traditional cooling solutions to be used in data centres, server rooms and other IT environments to cope with increasing heat loads. As a result, sustainability is sacrificed, and facilities can experience breakdowns, unplanned interruptions and skyrocketing energy bills.
However, there are many new air- or water-cooling methods: direct or indirect, standard or customized solutions… But what are the essential aspects to consider when choosing between the different cooling systems?
A wide range of cooling solutions:
The advanced thermal management solutions available today offer the richness, flexibility and modularity to meet the specific needs of each application and the challenges presented by the thermal load of various IT equipment.
There are four main cooling methods on the market:
Air cooling: heat is transferred directly to the ambient air, a classic cooling technique that is very common in data centres.
Indirect water cooling: heat is transferred indirectly to the water via an air/water heat exchanger located inside the row or a single cabinet.
Direct water cooling: heat is transferred directly to a heat transfer element attached to the equipment, such as a cold plate.
Hybrid water cooling (direct and indirect): the most energy-intensive components benefit from selective liquid cooling by direct contact, while the rest of the cabinet is cooled by a secondary air/water device, such as a cooling rear door.
It is evident that air cooling is becoming less and less feasible in high-density data centres, as heat loads increase as well as the densification of server racks that impedes air circulation. Air-cooling solutions can typically manage a maximum of 10 kilowatts economically. Data centres that try to remedy this by increasing the speed of air quickly turn into wind tunnels where it becomes difficult to work. In this context, the growing energy requirements accentuate the need for a liquid cooling system in the thermal management strategy.
Liquid cooling – the solution of the future?
For suitable applications, liquid cooling offers a high return on investment (ROI) and low total cost of ownership (TCO) compared to other cooling methods. In recent years, the range of liquid cooling solutions has expanded, helping to meet the specific protection needs of applications in virtually any environment. The liquid has a much greater heat transfer capacity than air – 3500 times greater – because it is denser.
Direct contact liquid cooling, which involves placing a cold plate directly on the processors inside the server, has the best energy efficiency. Thin cold plates used in direct contact liquid cooling have the advantage of taking up less rack space than conventional heatsinks. The cold plate also has internal micro-channels as well as an inlet and outlet where the liquid circulates to evacuate heat.
However, while liquid cooling offers considerable advantages for heat removal, it may be unnecessary to manage the entire heat load of a rack by this method alone because it is prohibitively expensive for some applications. In many cases, a hybrid solution – combining liquid and air cooling and effectively exploiting the high heat transfer capacity of fluids – is often more accessible and scalable.
Choose the right solution for the application
To determine the most efficient cooling technologies and configurations for a specific hardware, it is necessary to evaluate the current and future thermal profile of the environment, and then model the necessary infrastructure or configuration changes.
In doing so, several essential factors must be taken into account, including:
The placement of IT equipment: tightly coupled cooling systems, and direct liquid cooling systems within the data centre, air handling units, server room, or other IT environments is critical to the efficient use of available space and cooling capacity.
Current and expected cooling needs in the future: taking into account potential technological advancements, business growth and other goals.
Current or imminent standards: emerging trends and technology, as well as applicable regulations.
Resources compared to ROI and total cost of ownership.
Facility modernization timelines and investment planning.
Implementing the right solution:
Once the appropriate cooling solution has been determined, it will be necessary to gather the relevant data relating to the needs of the equipment to facilitate a smooth and optimal installation. This includes providing detailed information on equipment, configuration, thermal parameters, primary and secondary circuit design needs, distribution unit and architecture, etc. A routine maintenance plan will also need to be developed. In the case of a liquid cooling solution, this plan should include scheduled mandatory inspections and the ordering of spare parts in advance to ensure that the fluid inside the system remains in safe operating conditions.
Foremost Electronics, Platinum Distributor for nVent Schroff can supply all the elements high-performance IT equipment require with liquid cooling www.4most.co.uk
