Reconciliation of Wilson formulas and the equation of state for calculating the phase equilibrium of oil and gas

Koldoba Elena Valentinovna

Reconciliation of Wilson formulas and the equation of state for calculating the phase equilibrium of oil and gas

Koldoba E. V.

Koldoba Elena Valentinovna

Associate Professor, Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Chair of Computational Mechanics

Received: 25 Mar 2026

Published: 2025, vol. 29, issue 1, pp. 18–25

Download full text (In Russian)

Abstract

Iterative methods are used to compute phase equilibrium in multicomponent hydrocarbon solutions. Wilson’s formula is taken to calculate initial approximations, and the equation of state is taken to calculate chemical potentials or volatility. The paper proposes a method for adjusting Wilson’s formula to the equation of state used. It is shown that the consistent coeficients for heavy components are greater than for light ones. The approach allows one to construct a thermodynamically consistent system and eliminate some non-physical solutions and numerical instabilities.

Keywords: equations of state, Wilson’s formula, compution of phase equilibrium, multicomponent solutions, oil, numerical modeling

BibTeX

@article{IS-Koldoba2025,
  author  = {Koldoba, Elena Valentinovna},
  title   = {{Reconciliation of Wilson formulas and the equation of state for calculating the phase equilibrium of oil and gas}},
  journal = {Intelligent Systems. Theory and Applications},
  year    = {2025},
  volume  = {29},
  number  = {1},
  pages   = {18--25},
}

AMSBIB

\Bibitem{IS-Koldoba2025}
\by E.\,V.~Koldoba
\paper Reconciliation of Wilson formulas and the equation of state for calculating the phase equilibrium of oil and gas
\jour Intelligent Systems. Theory and Applications
\yr 2025
\vol 29
\issue 1
\pages 18--25
\lang In Russian

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