| 摘要 |
In a diesel engine, heavy EGR lowers a combustion temperature, which greatly prolongs an ignition delay period and all fuel is injected within the ignition delay period, thereby performing a low-temperature premixed combustion. A crank angle from a fuel injection completion to an ignition start is made less than 15 degrees by advancing a fuel injection timing and/or prolonging a fuel injection period. As a result, an equivalent ratio distribution in a combustion chamber at an ignition start is controlled such that an equivalent ratio in the vicinity of a cylinder center is richer than in the vicinity of a cylinder wall and the equivalent ratio gradually changes from the cylinder center to the cylinder wall. <IMAGE> |
