Abstract
In 1960, E. H. Brown defined a set of characteristic curves (also known as ideal curves) of pure fluids, along which some thermodynamic properties match those of an ideal gas. These curves are used for testing the extrapolation behaviour of equations of state. This work is revisited, and an elegant representation of the first-order characteristic curves as level curves of a master function is proposed. It is shown that Brown's postulate-that these curves are unique and dome-shaped in a double-logarithmic p, T representation-may fail for fluids exhibiting a density anomaly. A careful study of the Amagat curve (Joule inversion curve) generated from the IAPWS-95 reference equation of state for water reveals the existence of an additional branch.
| Original language | English |
|---|---|
| Article number | 96 |
| Number of pages | 19 |
| Journal | International Journal of Thermophysics |
| Volume | 37 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - Sep 2016 |
Austrian Fields of Science 2012
- 101014 Numerical mathematics
- 104010 Macromolecular chemistry
Keywords
- Brown’s characteristic curve
- Ideal curve
- IAPWS-95 equation of state
- Joule inversion
- Joule–Thomson inversion
- Water
- THERMODYNAMIC PROPERTIES
- VIRIAL-COEFFICIENTS
- Joule-Thomson inversion
- STATE
- MIXTURES
- UNIVERSAL EQUATION
- Brown's characteristic curve