
681
30.1 Introduction
The diesel engine has a prevailing role in transporta-
tion applications due to its higher thermal efciency,
compared to other propulsion systems, and its engine
size exibility. However, it still remains a major pollut-
ing source, especially regarding particulate emissions.
To comply with increasingly stringent environmental
regulations, over recent decades, the diesel engine man-
ufacturers and the scientic community have strived
to increase thermal efciency and power output, while
suppressing gaseous and particulate emissions of pol-
lutants. Increasing the in-cylinder oxygen availability
is an effective method to impro ...