Investigation of the kinetic mechanism of nitrogen oxidation in an automotive engine with stratified mixing

The authors proposed the method of calculation, which allows to determine the local formation of nitrogen oxides in the combustion chamber of automotive gasoline engine with internal mixture formation for the modes with laminar organization of the charge. Heterogeneity of sharply stratified mixture the workspace of the combustion chamber is divided on the path of the flame propagation into areas with different (localized) air-fuel ratio. For Volkswagen AUX-type engine test calculations conducted, which results revealed that outcome of nitrogen oxides from the combustion of a stratified mixture is 2,2 times reduced in comparison with the traditional version of uniform homogeneous mixture. Discrepancy between calculated and experimental results does not exceed 8%, thus confirming the adequacy of a satisfactory calculation method.

car engines, direct injection gasoline, layer mixing, heterogeneous mixture, homogeneous mixture, calculation method