Description:DESCRIPTION
Technical Field of the Invention

The present invention pertains to the field of high-performance computing infrastructure, specifically to cooling systems for server hardware. It relates to methods and systems for retrofitting traditional air-cooled servers to function efficiently within immersion cooling environments.

Background of the Invention

Data centers and high-performance computing environments have traditionally relied on air-cooled servers to manage the heat generated during operation. While air cooling is widely used due to its simplicity and compatibility with existing infrastructure, it has significant limitations. As computing power and server density increase, air cooling systems struggle to dissipate heat efficiently, leading to higher energy consumption, reduced hardware reliability, and increased operational costs.

Immersion cooling has emerged as a superior alternative to air cooling, offering improved thermal management, energy efficiency, and noise reduction. By submerging server components in a non-conductive dielectric fluid, immersion cooling facilitates direct heat transfer, significantly reducing the thermal resistance between the server and the cooling medium. However, the adoption of immersion cooling is limited by the high initial costs and restricted availability of server models specifically designed for this technology.

Retrofitting traditional air-cooled servers for immersion cooling presents a practical solution to overcome these barriers. Air-cooled servers are widely available and cost-effective, with a mature manufacturing ecosystem that offers diverse configurations tailored to various performance needs. Modifying these servers for immersion cooling enables data centers to transition to more efficient cooling systems without discarding existing investments in hardware.

This approach offers a cost-effective and scalable pathway to adopt immersion cooling technology. It minimizes capital expenditures, leverages existing server infrastructure, and allows for a phased upgrade strategy, reducing downtime and operational disruption. By addressing key challenges such as thermal interface adaptation, component protection, and material compatibility, retrofitting provides an efficient and sustainable solution to meet the growing demands of modern computing environments. This invention bridges the gap between affordability and advanced cooling performance, paving the way for broader adoption of immersion cooling in high-performance computing.

Brief Summary of the Invention

The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.

It is the primary objective of the present invention is to develop a cost-effective method for retrofitting traditional air-cooled servers for seamless integration into immersion cooling systems.

It is yet another object of the invention to enhance server thermal performance, reliability, and energy efficiency using immersion cooling without requiring purpose-built infrastructure.

It is yet another object of the invention to provide a scalable and sustainable solution for transitioning data centers to advanced cooling technologies while minimizing downtime and capital expenditure.

According to an aspect of the present invention, a method for retrofitting traditional air-cooled servers to function effectively within immersion cooling environments, addressing the inefficiencies of conventional air cooling systems. Immersion cooling, which involves submerging server components in non-conductive dielectric fluids, offers significant advantages such as improved thermal performance, reduced energy consumption, and lower noise levels. However, the high cost and limited availability of purpose-built immersion-cooled servers have hindered widespread adoption of this technology. This invention bridges the gap by retrofitting readily available air-cooled servers, enabling data centers to achieve the benefits of immersion cooling without replacing their existing hardware.

In accordance with the aspect of the present invention, the retrofitting process involves a series of modifications to server components and configurations to optimize compatibility and performance in immersion cooling environments. Key steps include the removal of air-dependent components such as fans and mechanical drives, replacement of thermal interface materials with immersion-compatible alternatives, and sealing sensitive components to prevent fluid ingress. Additionally, firmware adjustments are made to disable fan control mechanisms and optimize thermal management for liquid cooling conditions. These modifications ensure efficient heat dissipation, protection against corrosion, and stable operation in the dielectric fluid.
In accordance with the aspect of the present invention, the use of programmable resistors provides precise control over the charging current by dynamically adjusting resistance based on the monitored parameters. This feature eliminates risks associated with high current flows, ensuring a safe and reliable charging process. Additionally, the system employs sequential relay activation, which introduces current incrementally, preventing sudden surges and protecting both the batteries and the charging infrastructure.

In accordance with the aspect of the present invention, it incorporates structural adaptations to the server chassis, such as the addition of handles or hoisting features for ease of insertion and removal in immersion tanks. Cable management and component repositioning further enhance accessibility and thermal efficiency. Comprehensive testing, including thermal performance analysis, signal integrity checks, and material compatibility evaluations, is conducted to validate the reliability and effectiveness of the retrofitted servers in immersion cooling environments.

By leveraging the existing infrastructure of air-cooled servers, this invention provides a cost-effective and flexible pathway to adopt advanced cooling solutions. It allows data centers to improve operational efficiency, reduce total cost of ownership, and achieve greater sustainability. The retrofitting methodology not only extends the lifecycle of server hardware but also facilitates a gradual and scalable transition to immersion cooling, making it an ideal solution for modern high-performance computing environments. This invention represents a significant step forward in the development of sustainable, high-efficiency data center technologies.

Further objects, features, and advantages of the invention will be readily apparent from the following description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings.

Brief Description of the Drawings

The invention will be further understood from the following detailed description of a preferred embodiment taken in conjunction with an appended drawing, in which:

Fig. 1 illustrates the method (100) for retrofitting traditional air-cooled servers to function efficiently in an immersion cooling environment, in accordance with an exemplary embodiment of the present invention.

Figure 2 illustrates a modified server chassis designed for immersion cooling, in accordance with an exemplary embodiment of the present invention.

Figure 3 illustrates the left-side and right-side views of the modified chassis, in accordance with an exemplary embodiment of the present invention.

Figure 4 illustrates the rear and top view of a modified server unit adapted for immersion cooling applications, in accordance with an exemplary embodiment of the present invention.

Detailed Description of the invention

It is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

The use of “including”, “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. Further, the use of terms “first”, “second”, and “third”, and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

According to an exemplary embodiment of the present invention, a method for retrofitting traditional air-cooled servers to operate efficiently within immersion cooling environments. Immersion cooling involves submerging server hardware in non-conductive dielectric fluids, which provide superior thermal management by directly dissipating heat from components. The retrofitting process outlined in this invention enables the use of widely available air-cooled server hardware, modified to overcome challenges such as material incompatibility, thermal inefficiencies, and fluid ingress.

1. Preparation and Cleaning
The process begins with disconnecting power and data cables, followed by a thorough cleaning of server components to remove dust and debris. Compressed air or suitable cleaning agents, such as isopropyl alcohol, are used to eliminate contaminants that could compromise the dielectric fluid. Non-compliant cables and connectors are replaced with immersion-certified alternatives, and unused connectors are sealed with thermoplastic materials to prevent fluid ingress.

2. Component Removal and Replacement
Air-dependent components, such as cooling fans, are removed, and fan emulators are installed to bypass server firmware requirements. Mechanical drives are replaced with solid-state drives (SSDs) or NVMe storage devices for reliability in liquid environments. Power supply units (PSUs) incompatible with dielectric fluids are replaced or modified, retaining features like pulse fan modulation to meet operational standards. Thermal interface materials (TIMs) are replaced with immersion-compatible options like indium foil or liquid TIMs to enhance heat transfer.

3. Component Sealing and Protection
Sensitive components, connectors, and printed circuit boards (PCBs) are sealed with conformal coatings made of immersion-compatible materials such as ethylene vinyl acetate (EVA) and amorphous polyalphaolefin (APAO). Labels are replaced with durable, coolant-resistant alternatives to prevent degradation and contamination.

4. Chassis Modifications
The server chassis is adapted for immersion environments by adding handles or hoisting features for easy tank insertion and removal. High-power components such as CPUs and GPUs are repositioned to align with the immersion fluid flow, optimizing thermal efficiency. Cable management improvements ensure flexibility and accessibility for maintenance.

5. Firmware and Software Adjustments
Server firmware is modified to deactivate fan control and thermal sensor alerts triggered by the absence of fans. Settings for continuous operation in turbo or overclocking modes are enabled to utilize the enhanced thermal capacity of immersion cooling. BIOS and IPMI configurations are adjusted to optimize server performance in liquid environments.

6. Testing and Validation
The retrofitted servers undergo rigorous testing to ensure compatibility and reliability. Material compatibility tests are conducted to identify potential degradation, swelling, or corrosion in components exposed to the dielectric fluid. Signal integrity tests verify the stability of critical components, and thermal performance tests evaluate the heat dissipation capability of the modifications. Burn-in tests and performance assessments, including PCIe and DDR validation, confirm the server's readiness for immersion deployment.

7. Deployment and Maintenance
The retrofitted servers are deployed into immersion tanks, ensuring secure installation and optimal fluid flow. Regular maintenance involves monitoring the dielectric fluid for contamination or degradation, with periodic filtration or replacement to maintain cooling efficiency. Routine inspections ensure the longevity and reliability of retrofitted components.

Reference to fig’s, Fig. 1 illustrates the method (100) for retrofitting traditional air-cooled servers to function efficiently in an immersion cooling environment. The process involves several steps:

Preparation and Cleaning (102): Disconnect power and data cables, remove contaminants from server components using compressed air or cleaning agents, and replace non-compliant cables with immersion-certified alternatives.
Component Removal and Replacement: Remove air-dependent components (e.g., fans), install fan emulators, replace mechanical drives with SSDs or NVMe storage devices, and modify power supply units (PSUs) to be compatible with dielectric fluids.
Component Sealing and Protection (104): Apply conformal coatings to sensitive components, connectors, and PCBs for corrosion protection, and replace labels with immersion-compatible alternatives to prevent contamination.
Chassis and Mechanical Modifications (106): Modify the server chassis with hoisting features for easier handling, reposition high-power components for optimized fluid flow, and improve cable management for maintenance accessibility.
Firmware and Software Configuration (108): Adjust server firmware to disable fan control and thermal sensor alerts, enable overclocking modes for enhanced performance, and configure BIOS and IPMI for immersion cooling environments.
Testing and Validation (110): Perform compatibility tests for materials, evaluate thermal performance and signal integrity, and conduct burn-in tests to ensure reliable operation.
Deployment and Maintenance (112): Submerge the retrofitted server into the dielectric fluid, monitor fluid for contamination, and perform routine maintenance and inspections to ensure long-term system performance.

Figure 2 illustrates a modified server chassis designed for immersion cooling, shown from a top view and an isometric 3D perspective. The chassis has been restructured to eliminate traditional air-based cooling components, such as fan mounts and airflow ducts, making it suitable for submersion in dielectric fluid. Key modifications include the addition of reinforced green support mounts at the front, likely intended for cable stabilization and modular component housing, and red-marked areas denoting revised component placement zones optimized for fluid flow and thermal management. The open architecture facilitates efficient immersion and removal from the cooling tank while maximizing fluid contact with high-power components such as CPUs and memory modules. These changes collectively enhance the chassis's compatibility with immersion cooling environments, ensuring improved heat dissipation and operational reliability.

Figure 3 illustrates the left-side and right-side views of the modified chassis, highlighting the integration of handle bars specifically designed to aid in immersion cooling operations. The handle bars are positioned at the bottom of the chassis, enabling easy manual lifting and safe submersion into a dielectric fluid tank. The left-side view includes precise dimensional annotations, showing evenly spaced intervals of 92.00 mm between structural features along the chassis length, culminating in an overall height of 648.20 mm. These standardized placements not only enhance mechanical symmetry but also ensure compatibility with immersion tank slots and lifting mechanisms. The handle bar design supports ergonomic handling, improving user safety and reducing strain during system maintenance or immersion cycles.

Figure 4 illustrates the rear and top view of a modified server unit adapted for immersion cooling applications. The design modification eliminates traditional active air-cooling components, such as external fans and heatsinks, optimizing the configuration for submersion in dielectric cooling fluid. The ports are including USB, VGA, network interfaces, and redundant power supply units, remain accessible and are highlighted for ease of identification and maintenance. The red-bordered sections denote areas where airflow paths or active cooling components were removed or sealed off, ensuring safe operation within a fluid environment. This structural refinement minimizes trapped air pockets and maximizes fluid contact for efficient heat dissipation. The server's layout is tailored for rack compatibility, durability, and operational stability under immersion cooling scenarios, contributing to enhanced thermal performance and system longevity.

TESTING
Material compatibility testing is a crucial step in the retrofitting process of traditional air-cooled servers for immersion cooling. It ensures that all materials and components within the server remain chemically and physically stable when exposed to dielectric fluids. These specialized, non-conductive liquids are used in immersion cooling systems to efficiently dissipate heat from high-performance computing equipment. However, interaction between the dielectric fluids and conventional server materials can result in degradation, swelling, corrosion, or contamination—ultimately jeopardizing performance and system reliability.

To mitigate these risks, rigorous compatibility testing was conducted on materials such as plastics, seals, thermal interface materials (TIMs), capacitors, and other electronic components. This testing identifies potential chemical reactions, mechanical failures, or material breakdowns and informs decisions on component selection or required modifications to ensure long-term stability in immersion-cooled environments.

Exatron's retrofitted immersion-cooled servers were benchmarked and evaluated over a 240-day test period. Samples were examined at 0, 1, 30, 90, 180, and 240-day intervals. The following tests and evaluations were conducted by the R&D team:
1. Visual Inspection and Cosmetic Assessment
o Objective: Detect visual degradation or abnormalities.
o Result: No visible degradation was noted. Microscopic inspection confirmed no discoloration, material swelling, or immersion fluid contamination.
2. Contaminant Deposition Check
o Objective: Assess deposition of plasticizers, debris, and other contaminants on components and evaluate their impact on thermal performance.
o Result: No foreign contaminants or deposition detected.
3. Thermal Performance Tracking
o Objective: Monitor component temperature over time and assess cooling efficacy.
o Results: Stable thermal performance observed.
 CPU Temperatures:
 Day 30: 47.0 °C
 Day 90: 48.4 °C
 Day 180: 47.2 °C
 Day 240: 48.0 °C
4. Mechanical Integrity Testing
o Objective: Evaluate physical robustness of structural components (sockets, clips, retention mechanisms, etc.)
o Result: No structural defects or failures observed.
5. Corrosion and Metallization Analysis
o Objective: Inspect for corrosion on interconnects, solder joints, and exposed metal parts including the chassis.
o Result: No signs of corrosion or solder deterioration.

After 240 days of continuous immersion, Exatron's retrofitted servers demonstrated full compliance with immersion cooling guidelines. The servers maintained operational reliability and material integrity, validating the robustness of the retrofitting methodology. Figure 4 (not shown here) includes magnified PCB views captured at different testing intervals.

RESULTS
The testing confirms that retrofitting traditionally air-cooled servers for immersion cooling is not only feasible but also economically advantageous. With proper selection of components and dielectric fluids, existing data centers can transition to liquid cooling solutions with minimal disruption.
Key outcomes include:
• No degradation or contamination of server materials.
• Stable thermal performance over extended periods.
• Mechanical and structural integrity preserved.
• No corrosion or electronic interconnect failure.

CONCLUSION
The retrofitting method proposed for adapting air-cooled servers to immersion-cooled environments constitutes a significant process innovation in the realm of data center cooling solutions. By leveraging standard, widely available server hardware and making targeted modifications, this technique offers a cost-effective, low-disruption path to adopt advanced liquid cooling.

This approach addresses critical challenges including:
• Material compatibility with dielectric fluids
• Optimized thermal management
• Structural adaptation for submerged operation, it enables data centers to:
• Extend the operational lifespan and reliability of existing assets
• Achieve notable energy efficiency improvements
• Lower overall total cost of ownership (TCO)
Measured Benefits:
• Up to 50% reduction in operating costs
• Up to 50 dB reduction in acoustic noise
• Up to 10% improvement in performance per watt
• Up to 10% improvement in performance per dollar

This retrofitting methodology addresses a long-standing gap in the industry by offering a scalable, adaptable solution that unlocks the benefits of immersion cooling without requiring a complete overhaul of infrastructure. It positions data centers to align with sustainability goals and cutting-edge cooling innovations.

By establishing this as a novel and valuable intellectual property, the invention lays the groundwork for widespread adoption of immersion cooling in mainstream high-performance computing environments, enhancing both technological value and economic sustainability.
, Claims:CLAIMS
I/We Claim:
1. A method (100) for retrofitting traditional air-cooled servers to function efficiently in an immersion cooling environment, comprising:
a. Preparation and Cleaning (102):
• Disconnecting all power and data cables from the server;
• Removing dust, debris, and contaminants from server components using compressed air or cleaning agents such as isopropyl alcohol;
• Replacing non-compliant cables and connectors with immersion-certified alternatives and sealing unused connectors with thermoplastic materials, including ethylene vinyl acetate (EVA), amorphous polyalphaolefin (APAO), and polyamide (PA);
b. Component Removal and Replacement:
• Removing air-dependent components, including fans, and installing fan emulators to simulate necessary signals for server boot operations;
• Replacing mechanical drives with solid-state drives (SSDs) or NVMe storage devices;
• Evaluating and replacing power supply units (PSUs) incompatible with dielectric fluids while modifying existing PSUs to maintain pulse fan modulation functionality;
• Replacing thermal interface materials (TIMs) with immersion-compatible options, such as indium foil or liquid TIM, to enhance thermal conductivity;
c. Component Sealing and Protection (104):
• Applying conformal coatings to sensitive components, connectors, and printed circuit boards (PCBs) to protect against corrosion, fluid ingress, and environmental degradation;
• Replacing labels with immersion-compatible alternatives such as etched labels or coolant-resistant tapes to prevent contamination;
d. Chassis and Mechanical Modifications (106):
• Adapting the server chassis to include handles or hoisting features for easy insertion and removal from immersion tanks;
• Repositioning high-power components, such as CPUs and GPUs, to align with fluid flow for optimized heat dissipation;
• Enhancing cable management to ensure flexibility, accessibility, and maintenance ease;
e. Firmware and Software Configuration (108):
• Modifying server firmware to disable fan control mechanisms and thermal sensor alerts triggered by the absence of fans;
• Enabling settings for continuous operation in turbo or overclocking modes to exploit the thermal capacity of immersion cooling;
• Adjusting BIOS and IPMI configurations to optimize server functionality in the immersion environment;
f. Testing and Validation (110):
• Conducting material compatibility tests to verify the stability of components exposed to dielectric fluids;
• Performing thermal performance evaluations, signal integrity checks, and structural inspections to confirm operational stability and reliability;
• Utilizing burn-in tests and diagnostic tools, including memory and processor tests, to validate system performance.
g. Deployment and Maintenance (112):
• Submerging the retrofitted server into the dielectric fluid and ensuring proper installation;
• Monitoring and maintaining the dielectric fluid for contamination or degradation through periodic filtration or replacement;
• Performing routine inspections to ensure the functionality and longevity of retrofitted components.

2. The method (100) as claimed in claim 1, wherein the thermoplastic materials used for sealing connectors and sensitive components are selected from ethylene vinyl acetate (EVA), amorphous polyalphaolefin (APAO), and polyamide (PA) to provide enhanced fluid ingress protection and environmental resistance.

3. The method (100) as claimed in claim 1, wherein the fan emulators simulate presence signals by grounding presence-detect pins or using pull-up resistors, ensuring compatibility with server firmware requirements.

4. The method (100) as claimed in claim 1, wherein the thermal interface material (TIM) is replaced with indium foil or immersion-compatible liquid TIM to optimize heat dissipation within the dielectric fluid.

5. The method (100) as claimed in claim 1, wherein the replacement of mechanical drives includes substituting spinning hard drives with hermetically sealed helium drives or SSDs, ensuring compatibility with immersion environments and enhanced data reliability.

6. The method (100) as claimed in claim 1, wherein the chassis modifications further comprise the integration of reinforced metal handles to support the weight of the server during insertion and removal in immersion cooling tanks.

7. The method (100) as claimed in claim 1, wherein the repositioning of high-power components ensures that the CPUs, GPUs, and other heat-generating elements align with fluid flow patterns to maximize cooling efficiency and thermal performance.

8. The method (100) as claimed in claim 1, wherein the firmware modifications include disabling redundancy fan settings and adjusting thermal sensor thresholds to prevent erroneous alerts during operation in the absence of fans.