As datacenter cooling technology evolves, liquid cooling is emerging as a viable solution to address the growing cooling challenges. The impact of heat on datacenter performance is significant. Excessive heat can cause equipment failures or reduced performance, and in extreme case could lead to a system shutdown. Cooling systems ensure that equipment operates within the recommended temperature range, preventing overheating and extending the lifespan of the equipment.
Understanding Liquid Cooling in Datacenters
Liquid cooling is an innovative solution that has gained popularity in datacenters due to its ability to manage the heat generated by high-performance computing equipment.
There are various types of liquid cooling techniques used in datacenters. One common design is direct-to-chip cooling, where a liquid coolant is directly supplied to the heat-generating components of servers and other equipment.
Another common technique is immersion cooling, where the entire server or IT equipment is submerged in a dielectric liquid coolant. This method provides enhanced heat dissipation capabilities.
Liquid cooling works in datacenter infrastructure by circulating the coolant through a closed-loop system. The coolant absorbs heat from the equipment and carries it away. The heated liquid is then cooled down using heat exchangers before being recirculated.
There are several benefits of liquid cooling in datacenters. Firstly, it allows for higher power densities, enabling the use of more powerful computing equipment in a smaller footprint, resulting in cost savings and increased efficiency. Liquid cooling also reduces noise levels as it eliminates the need for fans.
However, there are also drawbacks to consider. Liquid cooling systems can be more complex and expensive to install and maintain compared to traditional methods. The use of liquid coolant introduces the risk of leaks, which can potentially damage equipment. Additionally, specialized expertise is required to design and implement liquid cooling solutions.
The Evolution of Datacenter Cooling Technology
Datacenters have evolved significantly in terms of cooling technology. In the early days, datacenters relied on simple air conditioning systems to maintain optimal temperatures. However, as the demand for more powerful and energy-intensive computing systems grew, it became clear that more advanced cooling methods were needed.
Historically, datacenters used air cooling methods such as computer room air conditioning (CRAC) units and raised floor systems. These methods were somewhat effective but had limitations in terms of energy efficiency and scalability. As datacenters expanded and became more complex, the need for better cooling solutions became evident.
Liquid cooling systems, such as chilled water systems and direct-to-chip cooling, offer superior heat dissipation capabilities compared to traditional methods. By using liquid coolant to remove heat from server components, these systems can achieve higher cooling efficiency and lower energy consumption.
With the growing demand for high-performance computing, datacenters and datacenter cooling designs are continuously evolving to meet industry needs. Developments in datacenter cooling are focused on improving efficiency, reducing environmental impact, and increasing scalability. Innovations such as immersion cooling are gaining traction for their ability to efficiently cool high-density computing environments.
Why Liquid Cooling?
Advantages of Liquid Cooling:
- Efficiency: Liquid cooling offers superior heat dissipation capabilities compared to air cooling. By directly cooling the components with a liquid coolant, heat can be efficiently transferred away from sensitive equipment, reducing the risk of overheating and improving overall system performance.
- Energy Savings: Liquid cooling solutions can reduce energy consumption in datacenters. Less power is required to cool the facility, resulting in substantial energy savings, lower Power Usage Effectiveness (PUE) and lower operating costs.
- Immersion Can Cope with High Chip Wattage: Chips with a Total Dissipated Power (TDP) above 270 watts are difficult to cool with air alone. Given that TDPs are projected to eclipse 1,000 watts by 2025, liquid cooling is gaining traction in modern installations that serve AI and HPC applications.
- Accommodating Generative AI: The latest data center, GPU, and system designs to facilitate generative AI call for a change of approach to power and cooling. “We are entering entirely new territory in the world of data centers, where the levels of compute and power running through these systems are unprecedented,” said S. Jay Lawrence, CEO, Equus. “Implementing sustainable and efficient cooling methods has never been as important as it is now.”
Types of Datacenter Liquid Cooling Techniques
Several designs can be employed to effectively manage heat dissipation and ensure optimal performance. Three popular types of datacenter liquid cooling techniques are:
- Direct-to-Chip Single Phase Cooling: This technique involves circulating a single-phase coolant directly to the chips of the servers. By utilizing a liquid-to-air heat exchanger, the heat generated by the chips is efficiently transferred to the coolant, preventing overheating and maintaining reliable operation.
- Direct-to-Chip – Two-Phase Cooling: In this method, a two-phase coolant is employed to directly cool the chips. The coolant evaporates upon contact with the heat source, absorbing a significant amount of heat in the process. The vapor then condenses back into a liquid state, releasing the heat and repeating the cycle.
- Immersive Liquid Cooling – IT-Chassis Single-Phase Cooling: This technique involves immersing the entire IT-chassis in a dielectric liquid coolant. The coolant absorbs the heat generated by the servers, effectively dissipating it and keeping the components at optimal temperatures. This method provides exceptional cooling efficiency and can significantly reduce energy consumption.
One of the key elements of a liquid cooling infrastructure is the pumps. Pumps are responsible for circulating the coolant throughout the system, ensuring a constant flow of cooled liquid to the equipment. The coolant acts as a medium for absorbing and carrying away the heat generated by the equipment.
Maintenance and monitoring of liquid cooling systems are crucial to ensure their continued effectiveness. Regular maintenance includes tasks such as checking for leaks, inspecting pump performance, and monitoring coolant (levels and quality). Additionally, continuous monitoring of temperature, pressure, and flow rates helps detect any potential issues early on, allowing for prompt action and preventing system failures. Because of the importance of monitoring system performance and the status of pumps, Design Envelope technology from Armstrong adds an important element of value for data center operators. Design Envelope pumps dynamically adjust output to provide the exact pressure and flow required in the moment. The Pump Manager subscription service also provides detailed reports, alarms and data storage to help operators monitor and optimize cooling effectiveness and energy consumption.
It's worth noting that there are some challenges to be aware of when considering a liquid immersion cooling system.
Fluid Toxicity - One issue that has emerged in recent years is the toxic nature of the chemicals used. These toxicity problems relate mainly to two-phase immersion cooling.
Corrosion - Some of the fluids used in immersion cooling have turned out to be more corrosive than first thought.
Bacteria - Heat acts as a catalyst and can lead to more bacteria.
Leakage - Leaks can have severe consequences for data center equipment, so OEMs of immersion cooling solutions typically go to great lengths to prevent leakage.
Space - Immersion cooling places unique constraints on data center design. Immersion racks are often wider and deeper than traditional racks, so room reconfiguration may be required.
Even with all of the above challenges, liquid immersion cooling holds great promise for data center operators and owners. A recent report sites the experience of NTT Global Data Centers. The company deployed immersion cooling in a campus in Mumbai and has reported 30% better energy efficiency.
Where HVAC systems involve fluid flow, heat exchange, and the need for optimized performance and efficiency, Armstrong is a leader in developing and deploying advanced solutions to help customers achieve their goals. Liquid immersion coolant systems represent one more area in which Armstrong can offer leading expertise in helping achieve and maintain optimal performance. For information on how we can assist with your next project, please reach out to the nearest representative.
