Dynamic simulation of flash drums using rigorous physical property calculations

F. M. Gonçalves, M. Castier, O. Q F Araújo

Research output: Contribution to journalArticle

13 Citations (Scopus)


The dynamics of flash drums is simulated using a formulation adequate for phase modeling with equations of state (EOS). The energy and mass balances are written as differential equations for the internal energy and the number of moles of each species. The algebraic equations of the model, solved at each time step, are those of a flash with specified internal energy, volume and mole numbers (UVN flash). A new aspect of our dynamic simulations is the use of direct iterations in phase volumes (instead of pressure) for solving the algebraic equations. It was also found that an iterative procedure previously suggested in the literature for UVN flashes becomes unreliable close to phase boundaries and a new alternative is proposed. Another unusual aspect of this work is that the model expressions, including the physical properties and their analytical derivatives, were quickly implemented using computer algebra.

Original languageEnglish
Pages (from-to)277-286
Number of pages10
JournalBrazilian Journal of Chemical Engineering
Issue number2
Publication statusPublished - Apr 2007
Externally publishedYes



  • Differential-algebraic equations
  • Dynamic simulation
  • Equation of state
  • Flash
  • Hydrocarbons
  • Phase equilibrium

ASJC Scopus subject areas

  • Chemical Engineering(all)

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