In the planning and construction of data centers, the design of temperature control systems is particularly critical. It not only affects the stability of equipment operation but also directly impacts energy consumption and operational costs. As the core of temperature control, the selection of cooling methods for central air conditioning systems is especially important. Currently, the two most common cooling methods are cooling towers and dry coolers, which differ significantly in their principles, applicable scenarios, and operational characteristics.Fundamental Working Principles of Cooling Towers and Dry CoolersCooling towers operate as evaporative cooling equipment, utilizing the heat absorption effect of evaporation when water contacts air to dissipate heat. The specific process involves: high-temperature cooling water is delivered into the tower by pump, where a spray system atomizes it into fine droplets. These droplets undergo heat and moisture exchange with incoming air. Part of the water evaporates into vapor, absorbing substantial heat in the process and lowering the temperature of the remaining water. The cooled water is then recirculated back to the condenser of the refrigeration unit to complete the heat transfer cycle. This process relies on the latent heat of phase change in water, achieving high heat exchange efficiency and maintaining effective cooling performance even in high-temperature, high-humidity environments.Dry coolers are air-cooled devices, relying entirely on sensible heat exchange between air and the cooling medium to achieve temperature reduction. Refrigerant or cooling water flows through enclosed coils, while outdoor air is forced by fans to pass horizontally or vertically over the coil surfaces, removing heat through convection. Since no water evaporation occurs, dry coolers offer significant advantages in water consumption and water treatment requirements. However, their heat exchange efficiency is highly influenced by ambient dry-bulb temperatures, potentially reducing cooling capacity during hot weather.Environmental Suitability Analysis of Both DevicesCooling towers are suitable for scenarios with relatively abundant water resources and high cooling efficiency requirements. In humid and hot climates, their evaporative cooling mechanism maintains stable performance. However, cooling tower systems require water treatment equipment to prevent scaling, biofouling, and corrosion, resulting in relatively higher maintenance costs. Additionally, in low-temperature winter environments, anti-freeze measures such as installing heaters or partial drainage are necessary to prevent pipe bursts.Dry coolers are better suited for water-scarce regions or sites with stringent environmental requirements. Their lack of water replenishment and wastewater discharge needs gives them a clear advantage in arid areas or projects with high environmental standards. Simultaneously, dry cooler systems feature simple structures, lower maintenance demands, and excellent long-term operational stability. Their limitation lies in restricted cooling capacity during high summer temperatures, potentially requiring larger equipment specifications or auxiliary refrigeration methods, which may increase initial investment costs.Energy Consumption and Economic ComparisonFrom the perspective of operating energy consumption, cooling towers, due to their use of evaporative cooling, usually have lower power consumption for fans and pumps, resulting in higher overall energy efficiency, especially under moderate humidity conditions. However, the water consumption and chemical water treatment costs need to be included in the long-term operation and maintenance costs. Additionally, the maintenance and regular cleaning of the water system also require human and material inputs.Dry coolers consume no water but rely on fans to drive airflow. Fan power is typically substantial, especially during high-temperature seasons when full-speed operation is required, leading to higher electricity consumption. However, with the widespread adoption of variable frequency technology, modern dry coolers can adjust fan speed to accommodate load variations, reducing energy consumption during partial load conditions. In cold regions, dry coolers can also utilize natural cooling sources for free cooling, further saving energy.Regarding investment costs, cooling tower systems—which include pumps, water treatment units, and piping—may have lower initial expenditures, but long-term operational and maintenance expenses require careful evaluation. Dry cooler systems feature compact structures and relatively straightforward installation, though equipment costs can be higher, especially when larger heat exchange areas are required.Reliability and Maintenance RequirementsCooling tower operational reliability is significantly influenced by water quality. Improper water treatment can lead to scaling, corrosion, and microbial growth, impairing heat transfer efficiency and potentially damaging equipment. Consequently, regular cleaning, blowdown, and chemical dosing are required, necessitating higher maintenance frequency. Additionally, open cooling towers may pose risks of splash contamination and Legionella growth, requiring appropriate protective measures.Dry cooler is a fully enclosed system, which avoids maintenance issues related to water. Daily maintenance only requires keeping the fins clean and inspecting the fan. The maintenance workload is relatively small. However, the moving parts such as the fan and motor need to be lubricated and inspected regularly to ensure long-term stable operation. In areas with frequent sandstorms, the fins are prone to accumulate dust, and they need to be cleaned frequently to maintain the heat exchange efficiency.System Integration and CompatibilityIn modern data center projects, the selection of cooling equipment also needs to take into account its integration capability with the overall air conditioning system. For instance, whether it supports variable frequency control, whether it can work in conjunction with natural cooling systems, and whether it is compatible with intelligent building management systems, etc. Cooling towers can achieve partial load optimization by adjusting the rotational speed of the fans and the frequency of the water pumps, while dry coolers can enhance the flexibility of regulation through multi-stage fan control and circuit design.Cooling towers and dry coolers each possess distinct advantages and disadvantages. Selection requires comprehensive evaluation of factors including climate conditions, water resource availability, energy pricing, operational capabilities, and long-term costs. In regions with moderate humidity or abundant water resources, cooling towers may offer greater energy efficiency advantages. Conversely, in water-scarce areas or regions with stringent environmental requirements, dry coolers may represent a more sustainable choice. Additionally, hybrid cooling systems—combining the strengths of both technologies and switching operating modes seasonally—are increasingly becoming the preferred solution for large-scale data centers.

As data centers continue to expand, traditional air cooling technologies increasingly struggle to meet the thermal demands of high-density computing equipment. Liquid cooling, with its superior thermal conductivity efficiency, has emerged as a popular choice for data center cooling. The Cooling Distribution Unit (CDU), a core component of liquid cooling systems, manages and distributes coolant to ensure stable operation of data center equipment within optimal temperature ranges. So how should a CDU be installed and managed? This article details the key installation and management considerations for CDUs when deploying liquid cooling in data centers.How a CDU WorksA coolant distribution unit (CDU) achieves strict coolant management by creating a secondary cooling loop isolated from the chilled water supply system (FWS), precisely controlling the cooling system's temperature, pressure, and flow rate. Its core components include pumps, heat exchangers, piping systems, and control systems. The primary side connects to the external cooling system, using electric regulating valve to regulate coolant flow into the CDU, thereby indirectly adjusting secondary-side temperatures. The secondary side connects directly to servers, with variable-speed pumps modulating circulation flow to ensure optimal heat dissipation efficiency.CDU Installation1. Pre-Installation InspectionBefore installing the CDU, conduct a thorough inspection to ensure compliance with data center specifications. First, verify the CDU's power requirements and confirm the data center possesses the necessary power capacity and type. Next, assess the CDU's feed type (top-fed or bottom-fed) and determine specific connection requirements, including pipe dimensions and fitting types. Additionally, understand the connection types needed for monitoring and integration with the data center's monitoring system.2. Installation LocationThe CDU's installation location significantly impacts its performance and maintenance accessibility. CDU equipment should ideally be installed outdoors, isolated from the main equipment room. If installed indoors, a waterproof containment barrier must be provided. Front and rear maintenance clearance should not be less than 800mm, while main equipment maintenance clearance should not be less than 1000mm.3. Piping ConnectionsWithin the data center, cold liquid pipes should preferably be routed under the floor, with adequate waterproofing, leak detection, and drainage measures implemented, along with corresponding alarm functions. When routing primary cooling loop pipes under the floor, the clear height under the raised floor should not be less than 600mm. When routing pipes above the floor, the clear height above the cabinet top should not be less than 600mm.4. Refrigerant Charging and CommissioningBefore charging refrigerant and commissioning the liquid circuit, complete pressure testing of the primary cooling loop liquid cooling system, inspect valve statuses, and finalize CDU electrical connections. Use a funnel during refrigerant charging to prevent spills, and assign personnel to monitor the liquid cooling system for leaks during replenishment. After reaching the specified pressure, maintain CDU operation for over 24 hours to observe the liquid level in the CDU reservoir.CDU Management1. Real-Time Monitoring and AlarmsThe CDU is equipped with integrated leak detection, intelligent flow monitoring, and alarm functions to ensure the safe operation of data center equipment. Through the real-time monitoring system, the CDU's operational status can be continuously tracked. Upon detecting anomalies such as signal loss or increased interference, the system immediately triggers an alarm to notify maintenance personnel for prompt resolution.2. Regular MaintenanceTo ensure long-term stable operation of the CDU, regular maintenance is essential. Periodically inspect the equipment's operational status and promptly replace aged or damaged components. For example, the CDU's filter (typically 50 microns) requires regular replacement to maintain coolant cleanliness and prevent contaminants or debris from compromising the integrity and performance of the server cold plate.30 Energy Efficiency OptimizationWith dynamic scalability and hot-swap design, the CDU easily adapts to cooling demands ranging from small server cabinets to hyperscale data centers. Each heat exchange module's 100kW capacity, combined with the plate heat exchanger's efficient thermal conductivity, significantly enhances cooling efficiency for high-power-density scenarios. Additionally, the constant-pressure module works in tandem with motorized ball valves to allocate cooling resources on demand, reducing energy consumption and improving the data center's Power Usage Effectiveness (PUE).When deploying liquid cooling in data centers, CDU installation and management are critical to ensuring stable system operation. Through scientifically sound practices—including optimal placement, piping connections, refrigerant charging, and commissioning—alongside real-time monitoring, regular maintenance, and energy efficiency optimization, CDU performance and reliability can be substantially enhanced. Looking ahead, as technology continues to advance, CDUs will play increasingly vital roles across broader applications, providing robust safeguards for the secure and stable operation of data centers.

In today's high-density computing and industrial sectors, thermal management is a critical requirement. There is a key component for advanced liquid cooling systems: the Coolant Distribution Unit (CDU). Whether you operate a high-performance data center, manufacturing facility, or research laboratory, the CDU is essential for unlocking equipment reliability, efficiency, and performance.            What is a Coolant Distribution Unit (CDU), and why is it so important?The Coolant Distribution Unit (CDU) serves as the central control and distribution hub within liquid cooling systems. It is a critical component of the cooling infrastructure in modern data centers and high-performance computing environments. Acting as the interface between the internal coolant loops of electronic devices—such as servers, GPUs, or power electronics—and the technical cooling system (TCS), it bridges the gap with the facility water system (FWS), enabling comprehensive thermal management.As processors and hardware capabilities grow increasingly powerful, and with the proliferation of AI and GPU chips, applications like deep learning, large model training, supercomputing, and edge computing rely on high-power data center GPU platforms. This has led to a dramatic increase in heat generation. Traditional air cooling is nearing its limits in terms of efficiency, noise, and space. The CDU enables precise direct-to-chip or immersion liquid cooling, significantly enhancing heat transfer efficiencyCore Components and Working Principle of CDUA typical CDU is an engineered assembly comprising several key components:Heat Exchanger: The core component where heat from the internal clean coolant loop is transferred to the facility water loop without mixing the two fluids.Pump: Drives the dedicated coolant to circulate in a closed loop through IT equipment, ensuring stable fluid flow to absorb device heat.Control System (PLC/Controller): The CDU's brain, monitoring temperature, flow, pressure, and leak detection. It adjusts pump speed and valve openings to maintain precise conditions.Monitoring Sensors: A sensors network for temperature, flow, pressure, and humidity.Fluid Distribution tubes: Fluid distribution tubes deliver coolant to various components within the CDU system, ensuring uniform cooling across all parts.Basic Working Principle: The cooling distribution unit (CDU) operates through a complex pump system that circulates coolant (typically water or a specialized fluid) via an intricate network of pipes or channels. This circulating coolant is critical for dissipating heat from key components such as processors and exchangers within large, high-power data center systems. The CDU integrates additional components like valves, filters, and monitoring mechanisms to optimize cooling efficiency and system reliability. Precisely calibrated valves enable dynamic adjustments to coolant distribution based on individual component demands, while filters ensure purity by screening out impurities and contaminants. Equipped with sensors, the CDU continuously monitors coolant parameters such as temperature, flow rate, and pressure levels, enabling real-time interventions to maintain optimal thermal performance and reliability within complex environments.The CDU pumps coolant to heat-generating devices such as servers, absorbs the energy, and then returns it to the external cooling source (such as a cooling tower, chiller, or dry cooler) for heat dissipation, thus forming a closed-loop cooling cycle.   CDU Classification           Types for Different NeedsClassified by design and integration level: Lori In-rack Liquid Cooling Coolant Distribution Unit (CDU) for Data CenterIn-rack CDUThe rack-level CDU compact units installed directly inside or beside server cabinets. Ideal for high-density equipment cooling in single cabinets or small clusters.   Data Center In Row Liquid Cooling CDURoom-level or Row-level CDULarger, more centralized units designed to cool entire rows, multiple cabinets, or dedicated rooms. The In-row or room level CDU offer greater cooling capacity and centralized management capabilities.Classified by cooling method: In Rack Air-liquid Hybrid Cooling CDU for CPU/GPU ServerLiquid-to-air CDUs (L2A CDU)Liquid-to-air CDUs (L2A CDU): Liquid-to-air CDU combines air cooling and liquid cooling technologies, deploying liquid cooling systems within or at the edge of server cabinets, but ultimately dissipating heat into the environment via air cooling. Its workflow is as follows: Coolant absorbs heat inside the server, the heated coolant exchanges heat with the internal heat exchanger via the CDU, and the final heat is expelled into the environment through data center air conditioning or fans. Compatible with existing air-cooled infrastructure, requiring minimal retrofitting for easy deployment and maintenance with lower operational costs. 300KW Liquid-to-liquid Centralized Cold Plate Cooling CDULiquid-to-Liquid CDUs (L2L CDU)Liquid-to-liquid CDU employs a fully liquid-cooled architecture, relying entirely on coolant for heat transfer. Server heat is transferred to the coolant within a closed loop via cold plates or immersion cooling. The heated coolant is then routed to the CDU, where it exchanges heat with external building-grade coolant through an exchanger. The cooled coolant is subsequently returned to the servers for reuse in the cycle.Advantages of the CDU Cooling System01Outstanding cooling efficiencyThe cooling efficiency of liquid is much higher than that of air, allowing for higher heat loads and quieter operation.02Energy saving and cost reductionSignificantly reduces reliance on room air conditioners (CRAC) and chillers, significantly lowers total energy consumption and costs.03Improved reliabilityStable and precise temperature control extends hardware lifespan and reduces failure rates.04Design flexibilitySupports higher power density and innovative cabinet/rack designs.05SustainabilityLower energy consumption directly contributes to reducing the carbon footprint and supports ESG goals.Lori CDU Solution: Designed for Outstanding PerformanceLori Open Type Liquid Cooling Coolant Distriution Unit (CDU)Liquid Cooling Row-mounted CDU for Supercomputing ServerSupercomputing Liquid Cooling In-Row CDULori More Liquid Cooling CDU SolutionsWhy choose Lori's CDU?Deep domain expertiseWe are experts in liquid cooling, not only manufacturers and suppliers of liquid cooling components (liquid cooling plates, manifolds, tubue, quick connectors, etc.), but also provide liquid cooling system equipment (CDU, dry coolers, liquid cooling cabinets, etc.).Comprehensive customization servicesWe collaborate with you to design a CDU solution that fully meets your thermal, space, and connection requirements.High quality and reliabilityOur products are manufactured to the highest standards to ensure stable operation in critical environments 24/7.Global support and servicesFrom initial consultation to deployment and maintenance, our team provides comprehensive technical support.Are you ready to revolutionize your thermal management?Contact Lori immediately! Let our experts show you how our custom-designed CDU solution can provide future security for your operations, reduce total cost of ownership (TCO), and offer you the key thermal management advantages you need.Contact us

A liquid cooling server is a server system that utilizes a liquid medium for heat dissipation. Unlike traditional air cooling technology, liquid cooling servers leverage the high thermal conductivity of liquids to rapidly transfer and dissipate heat generated within the server. Since liquids dissipate heat far more efficiently than air, liquid cooling servers maintain stable performance in high-density computing environments.Liquid cooling servers are typically categorized into two main types: direct liquid cooling and indirect liquid cooling. Direct liquid cooling involves the coolant directly contacting server components such as processors or memory. Indirect liquid cooling transfers heat from the server to the coolant via components like liquid cooling cold plates, manifold, and corrugated tubes avoiding direct contact. How Liquid Cooling Servers Work？The operation of liquid cooling servers is based on fundamental physical principles of fluid heat transfer. When servers operate under high loads, they generate significant heat that must be dissipated through an effective cooling system. Liquid cooling servers achieve heat dissipation through the following steps:Heat Generation and Transfer: Components like processors and memory within the server generate substantial heat during operation. The liquid cooling system absorbs this heat via the coolant.Coolant Circulation and Heat Dissipation: The coolant circulates within the server, carrying absorbed heat to heat dissipation devices. These devices—such as external cooling towers, heat exchangers, or other heat sinks—release the heat into the surrounding environment.Temperature Control and Feedback: Liquid cooling systems typically incorporate temperature sensors and control systems that continuously monitor internal server temperatures. They dynamically adjust coolant flow rates and temperatures as needed, ensuring the server consistently operates within optimal thermal parameters. Advantages of liquid cooling ServersCompared to traditional air cooling systems, liquid cooling servers offer significant advantages in multiple aspects:High-Efficiency Heat Dissipation: Fluids conduct heat far more efficiently than air, enabling faster and more effective heat dissipation within the same volume—particularly in high-density computing environments.Reduced Energy Consumption: Due to superior cooling efficiency, liquid cooling servers require relatively lower energy consumption. Studies indicate liquid cooling systems can lower a data center's PUE (Power Usage Effectiveness) value below 1.1, significantly reducing energy expenditure.Minimized Noise: Air cooling systems often require numerous fans for heat dissipation, resulting in considerable noise. liquid cooling servers utilize liquid cooling, reducing fan usage and effectively mitigating noise issues.Space Optimization: The compact design of liquid cooling systems reduces the cooling space required by traditional air-cooled systems, offering greater flexibility in data center layout planning.Extended Equipment Lifespan: A stable temperature environment helps reduce thermal stress on server components, prolonging equipment lifespan and lowering maintenance costs.Application Scenarios for liquid cooling Serversliquid cooling servers have extensive application scenarios, particularly suited for high-density computing and hyperscale data centers. Below are several typical application domains:Cloud Computing and Virtualization: Cloud platforms often process massive datasets with extremely high server density. liquid cooling servers provide stable thermal management support, ensuring efficient system operation.High-Performance Computing (HPC): In scientific computing, artificial intelligence, and machine learning, HPC clusters demand exceptional thermal management. liquid cooling servers meet these cooling requirements, enhancing computational efficiency.Edge Computing: With the rise of edge computing, small data centers and edge servers demand higher thermal efficiency. liquid cooling servers deliver effective cooling solutions within constrained spaces.Hyperscale Data Centers: liquid cooling servers play a particularly critical role in hyperscale data centers. These facilities deploy tens of thousands of servers, where liquid cooling technology significantly reduces energy consumption and thermal management costs.