Enhanced multiple injection for auto-ignition in internal combustion engines

摘要

An internal combustion engine has a fuel injection system capable of performing a multiple injection wherein a main injection event and a trigger injection event take place in this order in one cycle. With main injection, fuel is widely dispersed within a combustion chamber to create a main mixture for main combustion. With trigger injection, fuel is dispersed locally within the combustion chamber to create an ignitable mixture for auto-ignition. Auto-ignition of the ignitable mixture creates condition under which auto-ignition of the main mixture takes place. Fuel quantity and timing for each of main and trigger injections are varied corresponding to engine speed and load request to cause the main mixture to burn at a target crank angle after TDC of compression stroke.