Evaluation, Reduction, and Validation of a New Skeletal Mechanism for the Cofiring of NH3 and CH4

The evaluation and reduction of kinetic models for the cofiring of NH3 and CH4 can help to guide the application of NH3 and CH4 in industrial equipment. In this work, eight detailed kinetic models on the cofiring of NH3 and CH4 and 15 detailed kinetic models on the NH3 combustion are collected and evaluated based on error function and experiment measurement, and the detailed mechanism of 169 species and 1268 elementary reactions with the best overall performance was determined. By using two mechanism reduction methods of directed relation graph with error propagation (DRGEP) and DRGEP with sensitivity analysis (DRGEPSA), the skeletal mechanism of 45 species and 344 elementary reactions is achieved within the temperatures of 1000-2000 K, pressures of 1-60 atm, and equivalence ratios of 0.5-2.0. The skeletal mechanism is comprehensively validated and achieves good consistency with the detailed mechanism in predicting the laminar burning velocity, species concentration, and ignition delay time. The maximum relative error between the skeletal mechanism and the detailed mechanism is less than 13%.

Automated summary

The evaluation and reduction of kinetic models for the cofiring of NH3 and CH4 can guide the application of NH3 and CH4 in industrial equipment. Detailed kinetic models were collected and evaluated, and the best overall performance mechanism was determined. Simplified mechanism with good consistency in predicting burning velocity, species concentration, and ignition delay time was achieved.