天然气简化反应机理构建与验证

The ignition delay time, the laminar combustion speed of natural gas and the main species concentrations in the natural gas oxidation process were simulated by six detailed reaction mechanisms, and also compared with corresponding experimental data. The results showed that, compared with the other five detailed reaction mechanisms, Aramco 2.0 mechanism had the highest accuracy in predicting the ignition delay, laminar combustion and oxidation characteristics of natural gas. Based on Aramco 2.0 mechanism, an initial reduced reaction mechanism (including 21 species and 150 reactions) of natural gas (including CH₄, C₂H₆ and C₃H₈) was formed using the path sensitivity analysis, production rate analysis and reaction path analysis. At the same time, based on decoupling method, through combining the reaction mechanism of C₁- C₃ in the initial reduced reaction mechanism with the detailed reaction mechanism of H₂/CO and the reduced reaction mechanism of NOx, the reduced reaction mechanism of natural gas was constructed (including 40 species and 189 reactions). Compared with the corresponding experimental data, it was found that the reduced reaction mechanism can well predict the ignition delay, laminar combustion and oxidation characteristics of natural gas under various conditions.