Analysis of ignition processes in a fuel spray using an ignition model including turbulent mixing and reduced chemical kinetics

Abstract

In order to clarify the mechanism of fuel spray ignition, an ignition model was developed employing a stochastic turbulent mixing model and a quasi-global chemical kinetics model. Using this model, histories of heterogeneity in temperature and equivalence ratio of fuel/air mixtures were analysed. At low initial ambient temperatures, exothermic reactions begin in lean mixtures with equivalence ratios in a very narrow range. On the other hand, at higher air temperatures, mixtures with a variety of equivalence ratios ignite. This phenomenon can be explained by the dependency of mixture reactivity on the equivalence ratio and temperature. Based on these results, a discussion is given on the similarities and differences in the temperature dependency of ignition delays between sprays and homogeneous mixtures.

Keywords

ignition fuel spray stochastic turbulent mixing quasi-global chemical kinetics

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