Cryogenic Cryocooling and Liquefaction of gases

Cryogenic Cryocooling and Liquefaction of gases

Dr. Ben-Zion Maytal
Department of Mechanical Engineering, Technion-Israel Institute of Technology
Haifa 32000, Israel


Extended topics
1. Introduction.
The discipline of Cryogenics, and its chronology as “The Quest for Absolute Zero” (Paris, Geneva, Wroclaw, London, Leiden, Munich, Grenoble, Berlin, Oxford, and more).
Applications: Air separation and gas production, natural gas supply,
propulsion, defense, transportation, superconductivity, physics (CERN), super fluidity, magnetic levitation, medicine and cryosurgery and cryopreservation, space applications, nuclear fusion.
2. Joule-Thomson cryocooling: The integral JT effect, real gas properties, miniature and MEMS cryocoolers for IR sensors, open cycle with high pressure vessel, closed cycle, pure coolants, staging, mixed coolants and the associated synergy, Linde-Hampson cycle, Kleemenko-Missimer cycle, cryocooling by atmospheric air,
cryosurgical devices.
3. Cryocoolers and their unified perspective: The “interchanging” process of cryocooling, recuperative versus regenerative “interchanging”, Siemens-the inventor of cryocoolers, Joule-Thomson, reverse Brayton, Stirling, Solvay, Gifford-McMahon, Vuilleumier, Active Magnetic Regenerative Refrigerator (AMRR), sub Kelvin single shotadiabatic demagnetization, the deep sub-Kelvin dilution refrigerator (for 5 mK). Crryocooling versus Vapor Compression Refrigeration.
4. Liquefaction of gases: Linde-Hampson (single and dual pressure), Claude and its optimization, reverse Brayton (ideal and real), Kapitza, Heylandt, Collins. Liquefaction of quantum gases (helium, hydrogen, neon) and natural gas. Simon’s single shot liquefaction of helium. Satellite helium liquefaction.
5. Cryocoolers: general issues. Achievable temperatures, cascades of serial and parallel staging and the associated COP, FOM, hybrid cryocoolers, cooldown, compression ratio, reliability.
Case study: comparison of Stirling and Gifford-McMahon cryocoolers.
Case study: the non viability vortex tube cryocooler.
6. Special topics: the Third Law, space applications of cryocoolers, supefluid helium, thermal/mechanical/electrical properties of materials at cryogenic temperatures, mixtures of He-3 and He-4, sorption cryocoolers, Equations of State and real gas properties, Pulse Tube cryocoolers, superconductivity, Choked flow rates of real gases at low temperatures.

1/ Along the semester students (in couples) prepare a study on a special and focused subject related with the Cryocooling and Liquefaction of Gases.
2/ All these studies are presented at the last two meeting of the semester before all students of the class.
3/ This task weights 90% of the final grade.
4/ Three exercises along the semester based on EES (Engineering Equation Solver) software weights 10% of the final grade.
(EES is a software for thermodynamic simulation and fluid properties).

Text books
1. Miniature Joule-Thomson Cryocooling,
Ben-Zion Maytal and John Pfotenhauer,
Springer Publication, New York, 2012.
2. Cryogenic Engineering, Thomas Flyn,
Marcel Dekker Press, New York, 2005.
3. Cryogenic process Engineering,
Klaus Timmerhaus and Thomas Flynn,
Plenum Press, 1989.