Research progress on the reaction kinetics mechanism of hydrogen-blended fuel combustion

Hydrogen, a clean and efficient energy carrier, is becoming the core driving force for global energy transition and carbon emission reduction. This paper systematically reviews the research progress on the combustion reaction kinetics mechanisms of hydrogen and hydrogen-blended fuels (such as hydrogen-ammonia, hydrogen-methane, hydrogen-enriched syngas, and hydrogen-blended methanol). The focus is on analyzing these mechanisms' development, optimization, validation, and application. Through a comprehensive literature review, the optimal mechanism selections for different application scenarios have been identified: the Kéromnès mechanism exhibits the best overall performance for pure hydrogen combustion; the Stagni mechanism shows clear advantages in most environments for hydrogen-ammonia blended fuels; hydrogen-methane blended fuels demonstrate pressure-dependent characteristics, with GRI 3.0 performing best at low pressures (<10 atm) and the San Diego mechanism showing advantages at high pressures (>10 atm). The study reveals the limitations of existing mechanisms under high-pressure and high-temperature conditions, particularly in predicting intermediate product formation and pollutant emissions in complex operating conditions. Future research should focus on optimizing predictive capabilities under extreme conditions, improving reaction pathway identification, and enhancing the engineering practicality of mechanisms through multi-scale modelling approaches. This will provide theoretical support for applying hydrogen energy in the energy transition.