As AI applications drive the growing demand for high performance computing, servers are packing more processing power to handle increasingly complex and data-intensive tasks. This increased power results in higher heat generation, pushing the limits of traditional air cooling, especially in high-density rack environments.
Liquid cooling has become a critical requirement for modern data centers. Nearly one in five data centers (17%) already use liquid cooling, and an additional 61% of operations teams are considering its implementation. This trend reflects the industry's confidence in the effectiveness and efficiency of liquid cooling in managing heat from high-density IT racks.
However, integrating liquid cooling into existing systems can be a complex process. Since liquid cooling is a relatively new addition to the data center cooling landscape, overcoming the hurdles of this transition remains a challenge.
Explore the advantages of liquid cooling, key considerations for successful implementation, and available services to help you navigate the complexities of adding this technology into your data center cooling strategy.
Advantages of liquid cooling
1. Enhanced heat dissipation - Liquid cooling utilizes the higher thermal transfer capabilities of water or other fluids, which can be up to 3,000 times more effective than using air, to efficiently cool high-density racks. While it may require higher upfront costs, its ability to reduce energy consumption and extend equipment lifespan makes it a cost-effective choice in the long run.
2. Improved IT reliability and performance - Liquid cooling systems allow densely packed systems to operate at higher voltages and clock frequencies by efficiently dissipating heat, which helps maintain optimal thermal conditions.
3. Energy efficiency - Liquid cooling lowers power usage effectiveness (PUE), and enables efficient heat repurposing for building heating systems.
4. Reduced footprint - Liquid cooling also maximizes space utilization by enabling higher density within the same physical footprint. By efficiently managing heat, liquid cooling reduces the need for facility expansions, making it a valuable solution for data centers.
5. Lower TCO - Liquid cooling can lower the total cost of ownership (TCO) through higher density, increased use of free cooling, and improved performance per watt, according to the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE).
Key considerations
Although some new facilities will be specifically designed for AI workloads and liquid cooling, most installations will take place in existing facilities. Given the complex nature of liquid cooling systems, data center teams can benefit from full-service liquid cooling solutions that cover design, installation, startup, fluid management, maintenance, and digital management.
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Liquid Cooling Services
As heat surges in high-performance computing environments, the need for liquid cooling technologies in modern IT thermal management becomes critical.
To successfully implement liquid cooling and maximize its benefits, consider the following key factors:
1. Installation
The incremental addition of liquid cooling, whether in an existing data center or a new facility, often requires significant changes to the infrastructure. In brownfield projects, new piping systems, pumps, and heat exchangers may need to be installed, potentially requiring modifications to server racks to accommodate liquid cooling components. In greenfield projects, the infrastructure can be designed from the ground up.
Liquid cooling systems can optimize your facility's space by enabling denser server configurations within each rack. However, the cooling units themselves may require additional space and might require reconfiguring your facility's layout. For brownfield deployments, careful planning is critical to provide enough room for the new equipment without disrupting the current operations. In greenfield environments, space allocation and layout can be tailored to the cooling system, maximizing efficiency and performance from the outset.
To streamline this process, whether you’re retrofitting an existing data center or building a new one, consider partnering with experienced providers specializing in liquid cooling solutions. Vertiv offers comprehensive services that cover every aspect of the installation process for both brownfield and greenfield projects, including site assessment, project management, and design.
2. Cleanliness
The performance of liquid cooling systems can be significantly impacted by cleanliness because direct-to-chip cooling relies on clean, uncontaminated fluids to function efficiently. Any dirt, dust, or debris introduced during installation or servicing can contaminate the coolant, impact server operations, reduce thermal performance, and lead to potential system failures.
Data centers house sensitive electronic equipment that can be adversely affected by dust and other contaminants. During the installation or servicing of liquid cooling systems, it is crucial to maintain cleanliness within the fluid circuit to prevent contamination of the liquid inside the cold plates.
Following strict cleanliness standards and protocols during the installation and servicing of liquid cooling systems helps meet local regulatory requirements and maintain warranty.
3. Commissioning
Commissioning involves verifying that the liquid cooling system operates as intended and meets the specified performance criteria. This process includes testing and validating system components, fluid flow control, control loop tuning, and overall functionality under real operating conditions.
It also helps identify and address potential issues or defects in the system before it becomes fully operational. This includes detecting leaks, verifying system maximum working pressure, facilitating system-wide fluid distribution, and cross-checking functional parameters from the unit-level to the system-level of operations.
Through commissioning, adjustments can be made to optimize the system's performance, such as fine-tuning the system control loop, adjusting temperature and pressure settings, and calibrating components for efficient cooling.
4. Fluid management
Proper fluid management primarily focuses on maintaining the chemistry of the coolant. This involves taking regular fluid samples and conducting laboratory analyses to monitor and adjust the chemical balance by adding inhibitors as needed.
Effective fluid management reduces the risk of contamination, helping prevent issues like blockages, corrosion, and reduced thermal performance. Regular monitoring and corrective actions keep the fluid clean and free of impurities and help maintain fluid quality over the system’s lifespan.
5. Recurring services
Recurring services help identify and address potential issues before they lead to system failures. It also helps maintain the lifespan of the liquid cooling system and its components.
Additionally, regular servicing helps optimize system efficiency by cleaning filters, adjusting settings, and making necessary upgrades, which can also contribute to energy savings. Compliance with industry standards and safety regulations is maintained through periodic checks, and thorough documentation provides valuable insights into the system's condition over time.
By keeping the system in good condition and addressing wear and tear promptly, recurring services can reduce the need for costly repairs or replacements.
6. Spare parts
Having spare parts readily available enables quick resolution of issues, minimizes downtime, and maintains continuous operations in your facility. With Vertiv’s global service presence and over 3,500 service field engineers, problems can be addressed swiftly. The extensive network reduces lead times and prevents operational disruptions, enabling immediate action and avoiding prolonged periods of reduced cooling capacity.
Establishing a spare parts inventory also eliminates the need for emergency repairs or expedited shipping.
7. Digital Asset Monitoring
Liquid cooling solutions are rapidly becoming essential for maintaining optimal performance in today’s high-density applications. As a result, real-time monitoring and control are more important than ever, requiring digital services that can collect and analyze vast amounts of data at high frequencies. These capabilities lay the groundwork for condition-based maintenance (CBM), where maintenance activities are triggered by equipment health and usage data rather than fixed schedules.
These digital services are critical for maintaining uptime and safeguarding equipment in environments where even small deviations in temperature, flow rate, or pressure can lead to performance degradation—or worse, system failures. By integrating high-resolution data, advanced monitoring, and AI/ML-driven analytics, digital asset monitoring solutions enable condition-based maintenance strategies. As a result, operators can intervene at the right time with targeted actions, extending the life of crucial cooling components and ensuring continuous, optimized operation of high-performance computing environments.
Exploring liquid cooling options
Several liquid-cooling technologies are available to meet the cooling needs of high-density racks. However, installing liquid cooling can be complex. Data center teams will want to work with a partner to address key issues, such as plumbing requirements, cooling distribution, custom design elements, risk mitigation strategies, and the solution architecture of the integrated systems within the liquid loop.
Here are some liquid cooling options to consider:
Rear-door heat exchangers
Rear-door heat exchangers utilize the high thermal transfer properties of liquid without requiring a liquid-cooled server. Passive or active heat exchangers replace the rear door of the IT equipment rack with a liquid heat exchanger. In passive designs, server fans push heated air through a liquid-filled coil in place of the rear door, absorbing the heat before it enters the data center. Active heat exchangers use fans to draw air through the coils and remove heat from even higher-density racks. These systems can be used alongside air-cooling systems.
Coolant Distribution Units (CDU)
CDUs are an integral part of liquid cooling systems designed to increase overall system efficiency and reduce the total cost of ownership for high-density applications in the data center. CDUs deliver precisely controlled fluid to high-density IT equipment and remove excess heat from the system. By acting as a bridge between the facility's cooling infrastructure and the liquid-cooled servers, CDUs maintain optimal operating temperatures, prevent overheating, and enhance the overall efficiency of the cooling process.
- Liquid-to-Air: Existing perimeter air-cooled units remain essential components of the thermal infrastructure. A secondary fluid network (SFN) running from the CDU to the racks deliver optimal cooling capacity to support the liquid cooled servers. The liquid-to-air heat exchanger then rejects the heat into the data center to be captured by the facility’s existing air-cooling infrastructure, seamlessly integrating with existing thermal management solutions.
- Liquid-to-Liquid: This type of CDU uses a liquid-to-liquid heat exchanger to transfer heat from the IT equipment to the chilled water supply, which then rejects the heat outdoors. This enables efficient support for higher rack densities and optimal system conditions while offering easy and cost-effective deployment in any data center.
Both types feature filters, leak detection, intelligent flow monitoring, and system alarms to protect data center equipment.
Immersion cooling
Immersion cooling submerges servers in a conductive liquid, eliminating the need for air cooling and fans. There are single-phase and two-phase systems. In the single-phase system, servers are submerged in a conductive fluid, with heat removed by a Coolant Distribution Unit (CDU). The two-phase system, not yet commercially available, uses a fluid that boils on contact with hot components, turning into vapor that is then condensed back into liquid.
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Liquid cooling options for data centers
Data center operators are evaluating liquid cooling technologies to increase energy efficiency as processing-intensive computing applications grow.
Deploying liquid cooling
In summary, liquid cooling offers an efficient solution for managing heat in high-density computing environments. Its ability to deliver constant cooling across various temperatures provides consistent cooling performance, making it a compelling choice for modern data centers. However, successful implementation demands more than technology—it requires a comprehensive approach.
Vertiv’s Liquid Cooling Services address this challenge by offering assessment, design, installation, ongoing maintenance, as well as fluid and digital management for 100% uptime and peak performance, with compliance to global efficiency standards for thriving data centers.
If you have further questions or need personalized advice, contact us about Liquid Cooling Services.
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