Solution of the isochoric-isoenergetic flash problem by direct entropy maximization

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

A new algorithm to find the phase equilibrium conditions in systems with specified values of internal energy, volume, and number of moles of each component present (isochoric-isoenergetic flash problem) is proposed. The core of the procedure consists of maximizing the system entropy by iterating on the values, in each phase, of internal energy, volume, and number of moles of each component. Analytical expressions for the physical properties and derivatives required by the calculations were generated by computer algebra. The algorithm tests for the possible need to add or remove phases during the course of iterations. The paper discusses possible numerical difficulties during application of the procedure and how to overcome them. The algorithm has shown to be robust and capable of solving multiphase equilibrium problems, avoiding trivial solutions.

Original languageEnglish
Pages (from-to)7-17
Number of pages11
JournalFluid Phase Equilibria
Volume276
Issue number1
DOIs
Publication statusPublished - 15 Feb 2009
Externally publishedYes

Fingerprint

flash
Entropy
entropy
internal energy
Phase equilibria
Algebra
iteration
algebra
Physical properties
physical properties
Derivatives

Keywords

  • Algorithm
  • Equations of state
  • Flash
  • isochoric-isoenergetic
  • Optimization
  • Phase equilibrium

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Physical and Theoretical Chemistry
  • Physics and Astronomy(all)

Cite this

Solution of the isochoric-isoenergetic flash problem by direct entropy maximization. / Castier, Marcelo.

In: Fluid Phase Equilibria, Vol. 276, No. 1, 15.02.2009, p. 7-17.

Research output: Contribution to journalArticle

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