Gas liquefaction
Refrigeration and heat valorizing : cryogenics

In the case of air liquefaction, one of the most common processes uses the Stirling cycle. The figures 2a and 2b represent the theoretical Stirling cycle in Clapeyron and entropy diagrams. This cycle ideally comprises two isothermal transformations in contact with the cold source (a → b) and the hot sink (c → d). The two isochoric transformations (d → a, b → c) are associated here with perfect thermal regeneration during gas transfer through the regenerative exchanger. In reality, an imperfect regeneration occurs, which can be represented on the same figures. But this doesn't change the principle. The real case lies between perfect...