From the chemical reaction kinetics of diesel engine combustion
the investigation into the low-temperature reaction of oxygen-enriched combustion was done by CHEMKIN. Two important low-temperature reactions
the dehydrogenation reaction and the oxygen-addition reaction
were numerically analyzed by the CFD three-dimensional combustion model coupled with the N-heptane oxidation kinetic model. The results show that oxygen-enriched combustion can promote the dehydrogenation reaction. At the compression TDC
the maximum mass fraction of C
7
H
15
produced by the dehydrogenation reaction in the oxygen-enriched combustion is 1.95 times
4.77 times and 291.58 times of in the ordinary combustion when the oxygen concentration is 23%
25% and 27%
respectively. The oxygen-addition reaction rate increase
s linearly with an increase in the oxygen concentration. In addition
oxygen-enriched combustion enhances the diesel engine thermal efficiency and generates more OH radicals
and accelerating the subsequent reactions at medium temperature and high temperature.
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references
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