Incorporating critical divergence of isochoric heat capacity into the soft-SAFT equation of state

Fèlix Llovell, Lourdes F. Vega, Mikhail A. Anisimov, Jan V. Sengers

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

In the critical region, widely used equations of state, including molecular-based statistical associating fluid theory (SAFT) equations, fail to quantitatively describe the critical anomalies affected by the diverging fluctuations of density due to their classical mean-field approximation. Description of some properties in the critical region, in particular vapor-liquid coexistence and isothermal compressibility, can be improved by fitting (multi) parameters of an equation of state to the properties obtained in accurate computer simulations. However, some anomalies in the critical region, which are caused exclusively by critical fluctuations, cannot be readily generated by this procedure. An example of a critical anomaly, completely absent in the mean-field approximation, is the divergence of the isochoric heat capacity. A simplified methodology for modifying the original soft-SAFT equation of state to take into account these anomalies is explored. Possible procedures for further improvement are mentioned.

Original languageBritish English
Pages (from-to)3073-3080
Number of pages8
JournalAIChE Journal
Volume61
Issue number9
DOIs
StatePublished - 1 Sep 2015

Keywords

  • Argon
  • Critical phenomena
  • Equation of state
  • Isochoric heat capacity
  • Renormalization
  • Soft-SAFT

Fingerprint

Dive into the research topics of 'Incorporating critical divergence of isochoric heat capacity into the soft-SAFT equation of state'. Together they form a unique fingerprint.

Cite this