Low-temperature heat transfer mediums for cryogenic applications

Background: Researchers and industrialists have grown interested in cryogenic technologies over the years. Cryogenic heat transfer has enabled new applications due to material properties and behaviour at very low temperatures. This domain is still underdeveloped and unfamiliar in various applications.Methods: This work discusses the recent progress on cryogenic mediums and their respective use in different heat transfer applications. After identifying what is commonly designated as a cryogenic medium, i.e., those with a boiling point below-150 & DEG;C, the different characteristics and features of such mediums are critically discussed.Significant findings: Liquid He and N2 were found to be the most used cryogenic mediums, mainly due to the very low temperature attained by liquid He, as the closest to the absolute zero, along with the low cost and high availability of liquid N2. The use of liquid-phase cryogenic in a single-phase state was found to be the most common application method. Two-phase applications of the cryogenic medium are mainly for use in a heat pipe, in which both latent and sensible heat is utilized. Cryogenic mediums are essential for critical and niche applications such as in aerospace, superconductivity, advanced machining and manufacturing methods, and more critically in many healthcare applications and advanced scientific research.

Automated summary

Researchers and industrialists are interested in cryogenic technologies due to the unique properties of materials at very low temperatures. This work discusses the recent progress and characteristics of cryogenic mediums in heat transfer applications. Liquid He and N2 are the most commonly used cryogenic mediums, with liquid He providing extremely low temperatures and liquid N2 being cost-effective and easily accessible. The single-phase application of cryogenic mediums is common, while two-phase applications are mainly seen in heat pipes. Cryogenic mediums are crucial for critical and niche applications in aerospace, superconductivity, advanced manufacturing, healthcare, and scientific research.