Chemical Kinetic Research on Flame Characteristics of Ethylene under High CO2 Concentration Atmosphere

A numerical study was conducted to understand the flame characteristics of ethylene under O2/CO2 atmosphere by detailed chemical kinetic models. Special interest is focused on the effects of CO2 on flame propagation velocity and ignition delay. A modified reaction mechanism was established, and the ability of the reaction scheme was evaluated through comparison with well-defined laboratory data in the literature. A key result of the study is that the flame temperature and flame speed are significantly reduced because of the chemical and thermal effects of CO2. The most important reactions as well as the dominant reaction steps under both O2/CO2 atmosphere and air atmospheres were also studied. It can be concluded that although the main reaction paths of fuel oxidation under both atmospheres are quite similar, the most important elementary reactions are different from each other. Besides, the same reactions assume great importance for ignition under air atmosphere become less qualified under O2/CO2 atmosphere.