Detailed mechanism generation. 1. Generalized reactive properties as reaction class substructures

This paper, the first in a series on the automatic generation of detailed hydrocarbon mechanisms for hydrocarbons, describes how generalized reaction types, specifically the 25 types outlined by Curran et al. for heptane and isooctane combustion, can be translated into general reaction classes. Each type description from Curran et al. ranges from specific, such as differentiating among 1degrees, 2degrees, and 3degrees centers, to nonspecific such as specifying intermediate specific as products. In the latter case, additional interpretation of the reaction type must be extrapolated from other sources. The types are translated to the substructure patterns representing reaction classes. The success of fully translating all the rate and structural information described in these reaction types as they are defined in the literature demonstrates the power of the approach used here. A comparison of the generated reactions using these 25 types with that of a hand-produced heptane mechanism showed that, aside from well-defined exceptions, the set of reactions were almost identical. Often just the elimination of selected species (and sometimes reactions) was enough to make them identical. A notable exception was the use of lumped species in the hand-produced mechanism. The purpose of this paper is to show that an established set of reaction type descriptions can be translated to reaction classes suitable for automatic mechanism generation. A further goal of this paper is to show that these classes can be used to generate a detailed mechanism that mimics a hand produced one.