An automatic procedure for the simplification of chemical kinetic mechanisms based on CSP

An algorithm is developed to generate simplified (skeletal) kinetic mechanisms from a given detailed one. The algorithm is able to replicate the dynamics of a user-specified set of species (chosen from the original set) when a finite set of sampling points, D, in the chemistry configuration space is given. The simplification procedure involves discarding elementary reactions and species that are deemed unimportant to the fast and slow dynamics of a set of specific scalars. The criteria used in deciding which elementary reactions or species to discard are based on the computational singular perturbation (CSP) method. The procedure involves applying the CSP analysis to each point in D and an algorithm to assemble the simplified mechanism, the validity of which extends to all points in D and is tailored for the set of specified scalars. This algorithm provides a convenient way to construct comprehensive simplified mechanisms, applicable over a wide range of parameters and combustion processes. The effectiveness of this new algorithm is demonstrated by constructing simplified mechanisms for three methane/air reactive systems: autoignition in a constant-pressure reactor, a premixed flame, and a counterflow diffusion flame.