Resumo

OLIVEIRA, J.A.F; DUARTE, M.M.L; FOLETTO, E.L  e  CHIAVONE-FILHO, O. Levenberg-marquardt method applied to the determination of vapor-liquid equilibrium model parameters. Lat. Am. appl. res. [online]. 2014, vol.44, n.4, pp. 319-324. ISSN 1851-8796.

In order to correlate and optimize experimental data either from the laboratory or industry, one needs a robust method of data regression. Among the non-linear parameter estimation methods it may be pointed out of Levenberg, which applies the conversion of an arbitrary matrix into a positive definite one. Later, Marquardt applied the same procedure, calculating λ parameter in an iterative form. The Levenberg-Marquardt algorithm is described and two routine for correlating vapor-liquid equilibrium data for pure component and mixtures, based on this efficient method, have been applied. The routines have been written with an interface very accessible for both users and programmers, using Python language. The flexibility of the developed programs for introducing the desired details is quite interesting for both process simulators and modeling properties. Furthermore, for mixtures with electrolytes, it was obtained a coherent and compatible relation for the structural parameters of the salt species, with the aid of the method and the graphical interface designed

Palavras-chave : Nonlinear Regression; Levemberg-Marquardt Method; Vapor-Liquid Equilibria; Mixed Solvents Electrolyte Systems.