Formation mechanism of PAH and soot in diffusion flames of ethylene with methane addition
WANG Zhen, JIANG Peng, ZHOU Mengxiang, WANG Yu
1. School of Automotive Engineering, Wuhan University of Technology, Wuhan, Hubei 430070, China; 2. Hubei Provincial Collaborative Innovation Center for Auto Parts Technology, Wuhan University of Technology, Wuhan, Hubei 430070, China
Abstract：The reaction kinetics mechanisms of KAUST PAH mechanism 2（KM2） and AramcoMech are commonly used to simulate and predict the generation of polycyclic aromatic hydrocarbon(PAH) and soot. The two kinetics mechanisms were evaluated based on the flame multiparameter measurement data using methane mixed with ethylene opposed diffusion flame as research carrier. The results show that the two mechanisms can accurately predict the thermochemical structure of methane mixed with ethylene diffusion flame. However, the prediction performance of the influence of methane mixing on PAH and soot generation is poor. Neither mechanism fails to predict the inhibition of PAH and soot generation in methane mixed with ethylene flame. Comparing the similarities and differences of PAH and soot generation paths between the two mechanisms, it is found that both mechanisms overestimate the sensitivity of propargyl radical（C3H3·）generation to methane blending. The flame multiparameter measurement data are helpful to further optimize and verify the reaction mechanism of methane fuel.
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