Compression ignition internal combustion engine

A compression ignition internal combustion engine having an exhaust gas recirculation system for recirculating exhaust gas into an intake system, the engine comprising:

• supplying means for injecting fuel through injection holes at a substantially constant injection rate to atomize the fuel so that the fuel is easily vaporized and to make the fuel penetrate an atmosphere inside a cylinder of the engine, whereby the supplying means provides a spatial distribution of the injected fuel in which mixing of the fuel and air progresses as the fuel recedes from the injection hole along an injection direction and the fuel reaches a premixing space where the fuel is premixed with the air;
• and
• controlling means for performing combustion control for controlling oxygen concentration inside the cylinder so that a combustion space, in which the fuel is combusted, coincides with the premixing space, and for controlling a delay period extending from an injection start time to an ignition start time of the fuel so that the fuel is ignited while the fuel is injected and so that a ratio of a quantity of the fuel injected before ignition start to a total quantity of the fuel injected during the one injection falls within a predetermined range, wherein the controlling means performs the combustion control so that a pattern of a heat transfer release rate has no peak.