Principles of loop thermosyphon and its application in data center cooling systems: A review

Abstract With the development of big data and cloud computing technologies, data centers have grown rapidly worldwide. Although the commonly used data center cooling system (computer room air conditioning system, CRAC) is safe and reliable, it has a high energy consumption. Loop thermosyphon consumes less energy than the CRAC system and can be used in data center cooling system. This review presents the operating principles of the loop thermosyphon and its application in a data center cooling system. First, this review introduces the types of heat pipes and the operating principles of the loop thermosyphon. Second, the application of the loop thermosyphon in the room-, rack- and on-chip-level cooling of data center is reviewed. Finally, a combined compressor and loop thermosyphon system is introduced, which can be used to cool telecommunications base station. As the system can use cold ambient air directly as heat sink, it is more energy-efficient in comparison with using air conditioning alone as the cooling method. After reviewed and compared recent articles, we have indicated the imperfect points in recent researches and the future's development trend based on the results of researches and our experience. We think the points of this review is useful to the industrial applications.

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