Development and Verification of the New Simplified Mechanism for CH₄/O₂/CO₂ Laminar Premixed Flame under High Pressure

Abstract

To study the laminar premixed flame characteristics of methane under an O2/CO2 atmosphere in high pressure, a new simplified chemical mechanism (44 steps and 19 species) was extracted from the GRI-Mech 3.0 mechanism. The sensitivity coefficient analysis method is used to retain the elementary reactions that have great influence on the target parameters and remove other secondary elementary reactions. Meanwhile, the closeness of the simplified mechanism initially obtained was verified. The results of the laminar burning velocities, the distribution of the main species, and the ignition delay time were compared between the two mechanisms for the premixed flame and the ignition process. Overall, the simplified mechanisms performed fairly well over a wide range of pressure, equivalence ratio, and fuel mixture composition.