A Review on efficient thermal management of air- and liquid-cooled data centers: From chip to the cooling system

Khalaj, Ali Habibi; Halgamuge, Saman K.

doi:10.1016/j.apenergy.2017.08.037

Cited by 428 publications

(64 citation statements)

References 138 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among others, the DC cooling is a heat removal process which can be done with air-and liquidcooling systems. 8 The air-cooling methods are traditional DC cooling techniques which circulate the chilled air. 9 However, due to the low heat removal capacity of the air (37 W/cm 2 ), the air-cooled DC systems cannot be energy efficient and economically feasible for the rapidly developed ICT technologies, which have high heat flux; hence, the liquid-cooling DC methods have been being popular thanks to their high heat removal capacities (100 W/cm 2 ) in order to provide affordable and energy-efficient DC cooling operations.…”

Section: Introductionmentioning

confidence: 99%

“…9 However, due to the low heat removal capacity of the air (37 W/cm 2 ), the air-cooled DC systems cannot be energy efficient and economically feasible for the rapidly developed ICT technologies, which have high heat flux; hence, the liquid-cooling DC methods have been being popular thanks to their high heat removal capacities (100 W/cm 2 ) in order to provide affordable and energy-efficient DC cooling operations. 8,10 Another advantage of the liquidcooling DC systems is becoming independent from the ambient air conditions, namely, the changes in air temperature and relative humidity do not affect the system performance as remarkable as the air-cooled DC systems. Among the other liquid-cooling DC system types, the direct cooling systems are able to be customized according to the DC unit specifications and they can provide more satisfying temperature uniformity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Combined heat and power generation via hybrid data center cooling‐polymer electrolyte membrane fuel cell system

Kanbur

Duan

2020

Int J Energy Res

View full text Add to dashboard Cite

Summary Although there has been a lot of waste heat utilization studies for the air‐cooled data center (DC) systems, the waste heat utilization has not been studied for the liquid‐cooled DC systems, which have been rapidly gaining importance for the high‐performance Information and Communication Technology facilities such as cloud computing and big data storage. Compared to the air‐cooled systems, higher heat removal capacity of the liquid‐cooled DC systems provides better heat transfer performance; and therefore, the waste heat of the liquid‐cooled DC systems can be more efficiently utilized in the low‐temperature and low‐carbon energy systems such as electricity generation via polymer electrolyte membrane (PEM) fuel cells. For this purpose, the current study proposes a novel hybrid system that consists of the PEM fuel cell and the two‐phase liquid‐immersion DC cooling system. The two‐phase liquid immersion DC cooling system is one of the most recent and advanced DC cooling methods and has not been considered in the DC waste heat utilization studies before. The PEM fuel cell unit is operated with the hydrogen and compressed air flows that are pre‐heated in the DC cooling unit. Due to its original design, the hybrid system brings its own original design criteria and limitations, which are taken into account in the energetic and exergetic assessments. The power density of the PEM fuel cell reaches up to 0.99 kW/m2 with the water production rate of 0.0157 kg/s. In the electricity generation case, the highest energetic efficiency is found as 15.8% whereas the efficiency increases up to 96.16% when different multigeneration cases are considered. The hybrid design deduces that the highest exergetic efficiency and sustainability index are 43.3% and 1.76 and they are 9.4% and 6.6% higher than exergetic and sustainability performances of the stand‐alone PEM fuel cell operation, respectively.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Combined heat and power generation via hybrid data center cooling‐polymer electrolyte membrane fuel cell system

Kanbur

Duan

2020

Int J Energy Res

View full text Add to dashboard Cite

show abstract

“…There are two DC cooling types which are air-cooled and liquid-cooled DC systems. 5 The air-cooled DC systems are the traditional systems to release the heat from DC units. The liquid-cooled DC systems have been recently being popular thanks to their high heat removal performance.…”

Section: Introductionmentioning

confidence: 99%

Multi‐criteria thermoeconomic and thermodynamic assessments of the desalination‐integrated two‐phase liquid‐immersion data center cooling system

Kanbur

Duan

2020

Int J Energy Res

View full text Add to dashboard Cite

The waste heat management of the data center cooling systems has a significant share in the energy-efficient operations of the data centers. In this study, a new hybrid desalination-data center cooling system is proposed to reduce the cost drawback of the waste heat in the data center cooling operations. A two-phase liquid-immersion cooling unit is selected as the data center cooling method with the cooling load range of 0.7 to 1.5 kW. It is a promising solution thanks to the high heat flux removal performance but there is still a lack of research about waste heat management. The waste heat of the immersion cooling system is used to heat up the feed side of the desalination module. A direct contact membrane distillation system as preferred as the desalination module with the membrane area range of 5 to 75 cm 2. The proposed hybrid system is investigated according to the thermodynamic, economic, and thermoeconomic aspects. The thermoeconomic assessment is done concerning the unique exergy-cost matrix of the original design. The maximum thermal and exergy efficiencies are found as 64.5% and 53.7%, respectively. The daily distilled water rate can reach 6.13 kg at the highest cooling load and membrane area. Compared to the stand-alone data center cooling operation, the hybrid system has higher capital and operation costs. The payback period is found 3.72 years that means the proposed system is economically feasible for real applications. Also, the levelized product cost of the hybrid design is calculated in the range of 2.69 to 5.33 SGD/h. In the multiobjective optimization study, the best trade-off point is decided at the cooling load of 1.1 kW whilst the membrane area varies between 5.12 and 5.19 cm 2 .

show abstract

“…Since instability has always been one of the main challenges in the implementation of nanofluids, scientists have attempted continuously to improve the preparation techniques to have more stable nanofluids [2][3][4][5][6]. Most of the industrial applications of nanofluids are correlated with their higher effective thermal conductivity compared to common liquids; therefore, heat transfer characteristics of nanofluids have been the subject of many experimental and theoretical studies [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Moreover, the required pumping power in thermal systems depends on rheological properties; therefore, the rheological properties should also be evaluated to have a perfect design [24][25][26][27][28][29][30].…”

Section: Introductionmentioning

confidence: 99%

Nanofluids in the Service of High Voltage Transformers: Breakdown Properties of Transformer Oils with Nanoparticles, a Review

2018

View full text Add to dashboard Cite

The continuous development of electrical systems and high voltage transformers builds the need for looking for new insulating media or to improve the insulating properties of commercially available transformer oils (TO) by various modification techniques. One of these techniques is the modification of existing mineral oils by the addition of different types of nanoparticles in various concentrations. These types of materials, suspensions of nanoparticles called nanofluids, have found numerous applications in the energy industry, especially in heat exchanger systems and solar cells. Much research has been done on attempts to replace mineral oils (MO), which are harmful for the environment, with natural ester oils (NE), but to make this possible, it is necessary to improve the insulating properties of these oils, for example by adding nanoparticles. This paper presents an extensive overview of the insulating properties; including for AC, DC and the lightning impulse breakdown voltage; for both mineral and natural ester oils containing various type of nanoparticles (NP). It is presented that the use of nanofluids could improve the efficiency of existing high voltage infrastructures with a low financial cost.

show abstract

A Review on efficient thermal management of air- and liquid-cooled data centers: From chip to the cooling system

Cited by 428 publications

References 138 publications

Combined heat and power generation via hybrid data center cooling‐polymer electrolyte membrane fuel cell system

Combined heat and power generation via hybrid data center cooling‐polymer electrolyte membrane fuel cell system

Multi‐criteria thermoeconomic and thermodynamic assessments of the desalination‐integrated two‐phase liquid‐immersion data center cooling system

Nanofluids in the Service of High Voltage Transformers: Breakdown Properties of Transformer Oils with Nanoparticles, a Review

Contact Info

Product

Resources

About