Control apparatus for internal combustion engine

Abstract

An object is to achieve stable diesel combustion and improvement in the thermal efficiency of the diesel combustion in an internal combustion engine using a fuel having a relatively high self-ignition temperature. A control apparatus for an internal combustion engine includes a fuel injection valve capable of injecting fuel into a combustion chamber and an ignition device whose position relative to the fuel injection valve is set in such a way that it can ignite fuel spray directly. The apparatus causes pre-injected fuel to burn and generates unburned residue of the pre-injected fuel in the combustion chamber by pre-injection performed at a predetermined pre-injection time during the compression stroke and ignition of pre-spray formed by the pre-injection by the ignition device. Then, the apparatus starts main injection at such a predetermined injection start time before the top dead center of the compression stroke that enables combustion to be started by flame generated by combustion of pre-injected fuel to cause the unburned residue of the pre-injected fuel and the main-injected fuel to burn by causing the unburned residue of the pre-injected fuel and the main-injected fuel to self-ignite and causing at least a portion of the main-injected fuel to burn by diffusion combustion.