“…The after-injection, taking place within milliseconds after the main injection, aims at afterburning all remaining solid particles, while the post-injection supports keeping proper temperature of the exhaust gas to ensure higher operating efficiency of the exhaust aftertreatment system. The abovementioned Multijet concept of fuel injection comprises five injection phases, but other systems, which now gain in popularity, divide the fuel dose into 7 or 8 parts [2,3,4,5,6].…”