Determination of rate parameters of key N/H/O elementary reactions based on H2/O2/NOx combustion experiments

Abstract

Literature experimental data were collected about hydrogen–oxygen combustion systems doped with NO, NO2 or N2O or about H2/N2O combustion systems. The data included ignition delay times, laminar burning velocities, and concentrations measured in flow reactors, JSRs and burner stabilized flames. In total, 4949 data points in 207 data sets from 35 publications were used. These experimental data were reproduced using sixteen NOx mechanisms. The performance of the Nakamura-2017, Glarborg-2018 and Zhang-2017 mechanisms were the best. Nine elementary reactions were selected from the Glarborg-2018 mechanism based on sensitivity analysis and the Arrhenius parameters (A, n, E) of these reactions were fitted not only to the indirect experimental data, but also direct experimental and theoretical determinations of the rate coefficients. This way more accurate rate parameters of these reactions could be obtained and the temperature dependent uncertainty of the rate coefficients was calculated. The Glarborg-2018 mechanism modified with the optimized rate parameters described the experimental data better than any other investigated reaction mechanism.