Numerical experiments with new metaheuristic algorithms in phase equilibrium problems

Abstract

In this work, we presented some numerical experiments with two recently proposed metaheuristics (symbiotic organisms search and water wave optimisation) in the parameter estimation of an excess Gibbs free energy model (the Wilson model, using vapour-liquid equilibrium data) and in the calculation of azeotropes (non-reactive and reactive azeotropes). Both problems are characterised by nonlinear algebraic systems with multiple solutions, converted into optimisation problems with non-negative merit functions. The numerical results indicated that these new stochastic optimisation algorithms are capable to find the expected solutions in these real-world problems with robustness and accuracy. Moreover, fluid phase equilibrium problems can be viewed as challenging and useful tests for new metaheuristics.