3. Maximum Inversion Temperature [K]
Gas
Maximum Inversion Temperature [K]
Helium-4 45
Hydrogen
205
Neon
250
Nitrogen
621
Air
603
Carbon monoxide
652
Argon
794
Oxygen
761
Methane
939
Carbon dioxide
1500
Ammonia
1994

4. Linde-Hampson Cycle Liquefier

5. How to cool gases?
1. Joule Expansion: adiabatic irreversible no work expansion
When mJ < 0, cooling occurs. All gases except ideal gas cool through this process.
2. J-K Process: adiabatic irreversible isenthalpic expansion
When mJK > 0, cooling occurs. Need to be inside the inversion curve (mJK = 0).
3. Adiabatic reversible expansion (isentropic expansion)

6. Temperature-Entropy
Helium 4