A fast algorithm of coexisting phases compositions calculation in binary systems

A simple fast algorithm of the conodes calculation in binary systems is proposed. The method is based on exact solution of the problem on common tangent to pair of approximating parabolas. Sequence of approximating parabolas pairs having second order tangency points on separated concave parts of free energy isotherm is generated. The sequences of the tangency points pairs conodes with approximating parabolas converge to equilibrium compositions of phases in binary systems. PACS: 64.75.-g; 64.10.+h; 05.70.Ce; 82.60.-s Key words: Phase equilibria; Free energy; Binary systems; Conode; Phase diagrams.