Detailed kinetic modeling of ethane oxidation

A detailed chemical kinetic model has been developed for ethane oxidation that is applicable over a wide range of temperatures and pressures. This model incorporates the results of recent ab initio studies of the important low-temperature pathways of the C2H5 + O2 reaction as well as several C2H6 + RO2 abstraction reactions. These results change significantly the nature of the chain-branching reactions in ethane oxidation. The temperature and pressure dependencies of the rate coefficients in the model are represented by Chebyshev polynomials. The model predictions were compared to a variety of data, which include different reactor types and cover a wide range of temperatures, pressures, and equivalence ratios. These experiments include high-pressure flow reactor studies of lean ethane oxidation, PSR studies of both lean and rich ethane oxidation at different pressures, shock-tube studies of ethane oxidation and pyrolysis, and low-pressure flame experiments. The current model, with no adjustments, describes the experimental data reasonably well. A first-order sensitivity analysis identified the most important reactions in each of the kinetic regimes. The implications of inclusion of the concerted elimination of HO2 from ethylperoxy on hydrocarbon ignition are discussed.