cryogenic engineering

Cryogenic engineering is a sub stream of mechanical engineering dealing with cryogenics, and related very low temperature processes such as air liquefaction, cryogenic engines (for rocket propulsion), cryosurgery. Generally, temperatures below cold come under the purview of cryogenic engineering.

Cryogenics may be considered as the recent advancement in the field of refrigeration. Though there is no fixed demarcation as to where refrigeration ends and cryogenics begins, for general reference, temperatures below –150c(120k) are considered as cryogenic temperature.{{Cite web |title=Cryogenics {{!}} Low-Temperature Physics & Applications {{!}} Britannica |url=https://www.britannica.com/science/cryogenics |access-date=2024-05-02 |website=www.britannica.com |language=en}} The four gases which mainly contribute for cryogenic application and research are (O2-B.P.90K), (N2-B.P.77K), (Helium-B.P.4.2k) & (H2-B.P.20K).{{Cite web |last=Kanojiya |first=Harsh |date=April 2017 |title=Design and Thermal Analysis of Rectification Column for Separation of Nitrogen and Oxygen using Rectification Column Method |url=https://www.ijirst.org/articles/IJIRSTV3I11127.pdf}}

The word "cryogenic" is derived from Greek κρύο (cryo) - "icy cold" + γονική (genic) – "having to do with production".{{Cite web |title=Cryogenics |url=http://www.iter.org/mach/cryo |access-date=2024-05-02 |website=ITER |language=en}}