Publications

The impact of injection timing on mixture preparation and chemical kinetics in low-temperature diesel combustion

Miles, Paul C.; Petersen, Benjamin R.; Sahoo, Dipankar S.

Mixture formation and the chemical kinetics of combustion are examined in an automotive diesel engine operating at 1500 rpm and a fuel quantity corresponding to 3 bar gross IMEP. Laser-induced fluorescence of a toluene fuel tracer is used to obtain quantitative in-cylinder distributions of the fuel-air equivalence ratio, and homogeneous reactor simulations employing detailed chemistry are used to examine the impact of kinetics. With advanced combustion timing, losses in combustion efficiency and work output are found to be dominated by deficiencies in the mixture preparation process. With retarded injection, however, the chemical kinetics of combustion is the limiting factor. Trends in engine-out emissions are consistent with the measured mixture distributions and the results of the simulations. Copyright © 2012 by the Japan Society of Mechanical Engineers.