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Show Additionally, this study seeks to identify the reactions that control the extent to which the chlorinated hydrocarbon is destroyed. The chemical kinetic mechanism that we employed is based on one that we developed for C3 hydrocarbons [2,3]. To this hydrocarbon mechanism, we added a submechanism that treats the reactions of chlorinated species and is based on the mechanism of Senkan and coworkers [4]. We modified the chlorinated hydrocarbon submechanism to reflect recent developments in the literature. For example, Fisher et al. [5] have considered the site-specific abstraction of H-atoms from chloroethane. Tsang [6] has recently reviewed many of the reactions involving chlorinated species. Gutman and coworkers [7,8] have performed fundamental studies on individual reactions involving chlorinated hydrocarbons. Much previous work has been performed on the chemical kinetics of chlorinated hydrocarbons. The inhibition of flames by chlorinated hydrocarbons has been investigated [9]. The flame structure of chlorinated hydrocarbons has been experimentally measured and numerically simulated [4,10-12]. The thermal degradation of chlorinated hydrocarbons in a fused silica reactor has been investigated by Dellinger [13]. Barat et al. [14] have studied the combustion of methyl chloride under jet-stirred reactor conditions. Koshland and Fisher [15] have performed a chemical kinetics modeling study of chlorinated hydrocarbons under flow reactor conditions and examined the relationships between destructive efficiency, carbon monoxide and other reaction intermediates. These studies have furthered the development of the chemical kinetic mechanism of chlorinated hydrocarbons. Numerical Model and Chemical Kinetic Mechanism Chemical kinetic mechanism The chemical kinetic model was based on a previous mechanism developed for the oxidation of hydrocarbon fuels which has been documented earlier [2,3]. We added a submechanism (Table I) for the oxidation of chlorinated hydrocarbons from Karra et al. [4]. For most of the reactions in Table I, the forward rate parameters are listed on one line, with the reverse rate parameters listed on the following line. In general, the reverse rate parameters are calculated from the forward rate parameters and thermochemistry. For those reactions listed with only an "=" sign in the reaction name, the reverse rate is not given specifically in the table, but was calculated from the thermochemistry database. Some modifications were made to the Karra et al. mechanism that are important to note. The species C12 and two reactions involving it, which were not present in the original mechanism, were added. These reactions are Cl + Cl + M = C12 + M (31) Cl + HCl (32) (Note that the reaction numbers listig on the right are from Table ~.) The rate for Reaction 31 is 2.0 x 10 exp(1.79 kcal/mole) cT6-mole- sec- l fr~m Lloy~ [161, The rate used for Reaction 32 is 8.6 x 10 3exp (-1.17 kcal/mole , cm -mole- sec- from Atkinson et al. [17]. -2- |