Parameterization of Reaction Mechanisms Using Orthonormal Polynomials

Abstract Recent methods for mechanism reduction convert large detailed chemical reaction mechanisms into small systems of differential or differential-algebraic equations. A possible further step is the parameterization of reaction mechanisms, i.e. the description of chemical kinetics by explicit functions, obtained by numerical fitting to the numerical solution of differential equations. A new parameterization procedure, based on orthonormal polynomials, is described which is well applicable for fitting high-order polynomials having few effective parameters. A program is provided for the generation of multivariate Horner equations. The method is illustrated by the parameterization of a recent version of the Oregonator, a skeleton model of the oscillating Belousov—Zhabotinsky reaction.