Abstract The data center’s server power density and heat generation have increased exponentially because of the recent, unparalleled rise in the processing and storing of massive amounts of data on a regular basis. One-third of the overall energy used in conventional air-cooled data centers is directed toward cooling information technology equipment (ITE). The traditional air-cooled data centers must have low air supply temperatures and high air flow rates to support high-performance servers, rendering air cooling inefficient and compelling data center operators to use alternative cooling technology. Due to the direct interaction of dielectric fluids with all the components in the server, single-phase liquid immersion cooling (Sp-LIC) addresses mentioned problems by offering a significantly greater thermal mass and a high percentage of heat dissipation. Sp-LIC is a viable option for hyper-scale, edge, and modular data center applications because, unlike direct-to-chip liquid cooling, it does not call for a complex liquid distribution system configuration and the dielectric liquid can make direct contact with all server components. Immersion cooling is superior to conventional air-cooling technology in terms of thermal energy management however, there have been very few studies on the reliability of such cooling technology. A detailed assessment of the material compatibility of different electronic packaging materials for immersion cooling was required to comprehend their failure modes and reliability. For the mechanical design of electronics, the modulus, and thermal expansion are essential material characteristics. The substrate is a crucial element of an electronic package that has a significant impact on the reliability and failure mechanisms of electronics at both the package and the board level. As per Open Compute Project (OCP) design guidelines for immersion-cooled IT equipment, the traditional material compatibility tests from standards like ASTM 3455 can be used with certain appropriate adjustments. The primary focus of this research is to address two challenges: The first part is to understand the impact of thermal aging on the thermo-mechanical properties of the halogen-free substrate core in the single-phase immersion cooling. Another goal of the study is to comprehend how thermal aging affects the thermo-mechanical characteristics of the substrate core in the air. In this research the substrate core is aged in synthetic hydrocarbon fluid (EC100), Polyalphaolefin 6 (PAO 6), and ambient air for 720 hours each at two different temperatures: 85°C and 125°C and the complex modulus before and after aging are calculated and compared.
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Immersion Cooling in Data Centers: A Comprehensive Review of Benefits, Challenges, and Future Directions
Immersion cooling has emerged as a promising solution for the escalating thermal management challenges in the contemporary and modern (next generation) data centers, where traditional air-cooling systems are increasingly inadequate due to rising power densities in microprocessors. The evolution of immersion cooling technologies, highlighting their benefits and the challenges associated with their implementation, is explored in this review. Two-phase microchannel cooling has often been cited as a highly efficient alternative, which can help achieve significant energy savings over air cooling. Subsequent studies have expanded on methods like refrigerant touch cooling, thermosiphon systems, and geothermal immersion cooling. All these strategies can help achieve enhanced energy efficiency, reduced operational costs, and improved Power Usage Effectiveness (PUE). Immersion cooling has been demonstrated to support denser CPU packaging and meet the demands of high-performance computing environments. Despite these advantages, challenges persist, including the need for specialized infrastructure, potential risks related to liquid handling, and integration with existing systems. Advances in environmentally friendly cooling fluids and optimized airflow management have begun to mitigate some of these issues. To fully realize the potential of immersion cooling, future research endeavors should focus on developing standardized protocols and best practices to facilitate its widespread adoption. Enhancing the compatibility of cooling fluids with a broader range of hardware components will be crucial, as will designing systems that are easier to integrate with existing data center infrastructure. Exploring hybrid cooling solutions that combine immersion cooling with other efficient methods could offer additional benefits. Further investigation into the long-term reliability, maintenance requirements, and environmental impacts of immersion-cooled systems is essential. Integrating immersion cooling with renewable energy sources and waste heat recovery systems could also enhance sustainability and operational efficiency (e.g., for thermal desalination and wood drying applications). The literature reports can be utilized to identify a clear trend toward adopting immersion cooling as a key strategy for improving energy efficiency and thermal management in data centers. Hence, ongoing research and development efforts need to be redirected to overcoming these remaining obstacles, thus paving the way for more energy efficient data center operations with reduced footprint for water and power consumption in the future; while also improving the sustainability, reliability, robustness, and resilience of these platforms.
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- Award ID(s):
- 2401943
- PAR ID:
- 10654765
- Publisher / Repository:
- Begellhouse
- Date Published:
- Page Range / eLocation ID:
- 1513 to 1533
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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