Immersion Cooling of Digital Computers
01 Jan 1994-pp 539-621
TL;DR: In this paper, the theory and practice of direct liquid cooling of microelectronic components is discussed, and a morphological analysis is suggested for the classification of liquid-cooling concepts.
Abstract: The present work reviews the theory and practice of direct liquid cooling of microelectronic components. A morphological analysis is suggested for the classification of liquid-cooling concepts. While both immersion and microgroove cooling of chips are discussed, the emphasis is on immersion cooling. The performance of individual chips and liquid incapsulated modules, including the submerged condenser, is reviewed in detail, with data presented. Flow-through modules and falling-film techniques are also discussed. Finally, figures-of-merit for coolants are noted.
Citations
More filters
IBM1
TL;DR: This paper provides a broad review of the cooling technologies for computer products from desktop computers to large servers in terms of air, hybrid, liquid, and refrigeration-cooled systems.
Abstract: This paper provides a broad review of the cooling technologies for computer products from desktop computers to large servers. For many years cooling technology has played a key role in enabling and facilitating the packaging and performance improvements in each new generation of computers. The role of internal and external thermal resistance in module level cooling is discussed in terms of heat removal from chips and module and examples are cited. The use of air-cooled heat sinks and liquid-cooled cold plates to improve module cooling is addressed. Immersion cooling as a scheme to accommodate high heat flux at the chip level is also discussed. Cooling at the system level is discussed in terms of air, hybrid, liquid, and refrigeration-cooled systems. The growing problem of data center thermal management is also considered. The paper concludes with a discussion of future challenges related to computer cooling technology.
232 citations
Cites background from "Immersion Cooling of Digital Comput..."
...Although much work [29] has been done in this area, it is still a potential problem in pool boiling applications using fluorocarbon liquids to cool untreated silicon chips....
[...]
01 May 2016
TL;DR: In this article, the authors reviewed the changes in physical and chemical properties of information technology (IT) equipment materials like polyvinyl chloride (PVC), printed circuit board (PCB) and switching devices due to mineral oil to characterize the interconnect reliability of materials.
Abstract: This paper reviews the changes in physical and chemical properties of information technology (IT) equipment materials like polyvinyl chloride (PVC), printed circuit board (PCB) and switching devices due to mineral oil to characterize the interconnect reliability of materials. By submerging all of a server's heat-generating components in a dielectric liquid, creates the attack on reliability issues at the device level. The improved efficiency of mineral oil may offer simplicity in facility design compared to traditional air cooling and provide a means for cost savings. In spite of its improved cooling efficiency and cost savings, a mineral oil immersion cooling technique is still not widely implemented and suppliers are reluctant to jeopardize sales of existing air-based cooling system equipment. Only compelling physics regarding direct immersion cooling is not enough for data center operators. Many uncertainties and concerns persist regarding the effects of mineral oil immersion cooling on information technology equipment reliability. The paper presents useful information regarding the influence of mineral oil on the mechanical properties as well as chemical properties of a material. The changes in properties of mineral oil like kinematic viscosity and dielectric strength are also cited as an important factor and discussed briefly. The changes in mechanical properties like elasticity, hardness, swelling, and creep are being shown in the paper for thermoplastic materials. The chemical reaction between material and mineral oil as a function of time and temperature is also conferred. These are significant factors which are responsible for the reliability and compatibility of a material. The changes or modifications in materials of important parts in physical and chemical manner are also indicated. The relations between different dielectric oils and different materials provide us a comparative analysis for reliability and performance. Oil immersion cooling of data centers offers opportunities for enhanced reliability with even temperature conditions in operations as it minimizes common operational issues like: overheating and temperature swings in the system, fan failures in servers, noise, dust, air quality, corrosion, electrochemical migration, and whiskers will also be addressed. The reliability improvements are comprised of the reduction in corrosion & electrochemical migration like corrosive exposure and moisture reduction, reduction in environmental contamination like dust, debris and particulate reduction, stable and even thermal environment and tin and zinc whisker mitigation. These may lead to infer the significance of oil cooled data centers towards performance and savings in operating cost as per reliability aspect. The literature gathered on the subject and quantifiable data gathered by the authors provide the primary basis for this research document.
34 citations
Cites background from "Immersion Cooling of Digital Comput..."
...Efficient handing methods and cleanliness should be implemented and filtration of oil lessens the risk of particulate and dust contaminants [14]....
[...]
...Immersion oil cooling reduces and/or eliminates temperature, moisture, and contamination aspects [14], [13]....
[...]
01 Jan 2010
TL;DR: A review of the relevant passive and active thermal management techniques, the physical phenomena underpinning the most promising on-chip thermal management approaches are described in this article, where the authors focus on thin-film and miniaturized thermoelectric coolers, orthotropic TIMs/heat spreaders, and phase change microgap coolers for hot-spot remediation and thermal management of these nanoelectronic chips.
Abstract: The rapid emergence of nanoelectronics, with the consequent rise in transistor density and switching speed, has led to a steep increase in die heat flux and growing concern over the emergence of on-chip “hot spots.” The application of on-chip high heat flux cooling techniques provides a viable direction for the thermal management of such nanoelectronic components. Following a review of the relevant passive and active thermal management techniques, the physical phenomena underpinning the most promising on-chip thermal management approaches are described. Attention is devoted to thin-film and miniaturized thermoelectric coolers, orthotropic TIMs/heat spreaders, and phase-change microgap coolers for hot-spot remediation and thermal management of these nanoelectronic chips.
30 citations
23 citations
IBM1
TL;DR: A bibliography of 847 publications dealing with air cooled heat sinks for thermal enhancement of electronic packages is presented in this article, which also includes papers dealing with design and performance analysis of heat sinks, extended surfaces and adhesives for bonding heat sinks.
Abstract: A bibliography of 847 publications dealing with air cooled heat sinks for thermal enhancement of electronic packages is presented. The bibliography also includes papers dealing with design and performance analysis of heat sinks, extended surfaces and adhesives for bonding heat sinks. The papers are classified in several categories.
16 citations
References
More filters
TL;DR: In this paper, a water-cooled integral heat sink for silicon integrated circuits has been designed and tested at a power density of 790 W/cm2, with a maximum substrate temperature rise of 71°C above the input water temperature.
Abstract: The problem of achieving compact, high-performance forced liquid cooling of planar integrated circuits has been investigated. The convective heat-transfer coefficient h between the substrate and the coolant was found to be the primary impediment to achieving low thermal resistance. For laminar flow in confined channels, h scales inversely with channel width, making microscopic channels desirable. The coolant viscosity determines the minimum practical channel width. The use of high-aspect ratio channels to increase surface area will, to an extent, further reduce thermal resistance. Based on these considerations, a new, very compact, water-cooled integral heat sink for silicon integrated circuits has been designed and tested. At a power density of 790 W/cm2, a maximum substrate temperature rise of 71°C above the input water temperature was measured, in good agreement with theory. By allowing such high power densities, the heat sink may greatly enhance the feasibility of ultrahigh-speed VLSI circuits.
4,214 citations
TL;DR: In this paper, a simple expression for the space-mean Nu (or Sh ) for all Ra and Pr (or Sc) in terms of the model of Churchill and Usagi was developed.
1,618 citations
01 Jan 1951
1,114 citations
TL;DR: In this article, a regression analysis was applied to the nearly 5000 existing experimental data points for natural convection boiling heat transfer, which can best be represented by subdividing the substances into four groups (water, hydrocarbons, cryogenic fluids and refrigerants) and employing a different set of dimensionless numbers for each group of substances.
710 citations