Substantial efforts have been made recently in order to develop new strategies for the in-cylinder reduction of soot and nitrogen oxides (NOX) emissions from diesel engines. In small engines for automotive applications,these strategies include multiple fuel injections to improve fuel-air mixing and achieve combustion under conditions that do not favor emissions formation [1-5]. The main goal of this approach is the enhancement of fuel atomization and evaporation in order to create a more homogeneous fuel-air mixture in the cylinder (with reduced fuel-rich areas, where soot is produced). In addition, maintaining combustion at temperatures lower than approximately 2300 K is important for reducing the
nitrogen oxides formation