An algorithm for convergent solutions in vapor-liquid equilibrium calculations using an equation of state

Ju Ho Lee, Jeong Won Kang, Seong Sik You, Chul Soo Lee

Research output: Contribution to journalArticle

2 Citations (Scopus)


In high-pressure vapor-liquid equilibrium calculations using an equation of state, two types of convergence problems may be encountered as the critical region is approached. One is the trivial solution in which compositions and densities for equilibrium phases become identical and the other is the divergence problem. In the present study, an efficient algorithm was proposed to remove these difficulties in the extended regions by introducing auxiliary loops for composition and pressure (or temperature) iterations. The algorithm was found to extend the region of convergence to near critical points efficiently without using the information on adjacent equilibrium points.

Original languageEnglish
Pages (from-to)34-41
Number of pages8
JournalFluid Phase Equilibria
Issue number1-2
Publication statusPublished - 2005 Aug 8



  • Equation of state
  • Trivial solution
  • Vapor-liquid equilibrium calculation

ASJC Scopus subject areas

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

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