Patent attributes
In an engine (10) comprising a fuel injector (12) which performs a post injection after performing a main injection into a cylinder and an exhaust valve (15) which opens and closes to discharge an exhaust gas, a controller (70) controls the fuel injector (12) to start the post injection during a period where a gas velocity in the cylinder along a cylinder axis increases after the exhaust valve (15) opens. A duration (t) of the post injection is controlled according to a crank angle at which the post injection is to be performed such that a breakup distance (L) at the end of which the injected fuel atomizes does not become larger than a distance (S) from an injection hole (12a) to a cylinder liner (10c), thereby ensuring that the injected fuel is supplied to an exhaust passage (23) without adhering to the cylinder liner (10c).
