A new species reduction method called the Level of Connection (LOC) was proposed and demonstrated. According to the LOC algorithm, a mechanism building procedure was started from the specified "interesting sets" of species. Strongly connected sets of species was identified on the basis of the normalized contribution of one species to the production rates of the sets of species and the normalized Jacobian. The demonstration was performed for a detailed ethylene oxidation mechanism consisting of 116 species and 635 elementary reactions, resulting in a specific skeletal mechanism consisting of 46 species and 274 elementary reactions, and a specific reduced mechanism consisting of 21 species and 14 global reactions. Calculations for a premixed flame structure using either the skeletal mechanism or the reduced mechanism show very close agreement with those obtained by using the detailed mechanism.

Key words: reduced mechanism, sensitivity analysis, directed relation graph, level of connection