Engine system, combustion control system, and operating method with close-coupled early pilots and cylinder temperature control

A direct-injection compression-ignition engine system comprising:

• an electrically actuated fuel injector structured to directly inject a fuel into a cylinder in an engine;
• an electrically actuated cylinder temperature controller;
• a combustion control unit in communication with the fuel injector and with the cylinder temperature controller, the combustion control unit being structured to:
• command actuation of the fuel injector to inject early pilot shots of the fuel into the cylinder during moving a piston in the cylinder from a bottom dead center (BDC) position to a top dead center (TDC) position in an engine cycle;
• command actuation of the fuel injector to inject a main charge of the fuel into the cylinder after injection of the early pilot shots;
• command actuation of the cylinder temperature controller to control a cylinder temperature timing such that the cylinder temperature timing in the engine cycle is varied relative to cylinder temperature timing in a previous engine cycle;
• and
• phase combustion of the early pilot shots, prior to the TDC position of the piston in the engine cycle, based upon the controlling of the cylinder temperature timing, and such that the phasing of combustion in the engine cycle is varied relative to phasing of combustion in the previous engine cycle.

A combustion control system for an engine comprising:

• a combustion control unit structured to command actuation of a fuel injector, for directly injecting a fuel into a cylinder in the engine, and a cylinder temperature controller, for controlling a cylinder temperature decoupled from a position of a piston within the cylinder;
• and
• the combustion control unit being further structured to:
• command actuation of the fuel injector to inject early pilot shots of the fuel into the cylinder during moving the piston from a bottom dead center (BDC) position to a top dead center (TDC) position in an engine cycle;
• command actuation of the fuel injector to inject a main charge of the fuel into the cylinder after injection of the early pilot shots in the engine cycle;
• command actuation of the cylinder temperature controller to control a cylinder temperature timing such that the cylinder temperature timing in the engine cycle is varied relative to cylinder temperature timing in a previous engine cycle;
• and
• phase combustion of the early pilot shots, prior to the TDC position of the piston in the engine cycle, based upon the cylinder temperature timing, such that the phasing of combustion in the engine cycle is varied relative to phasing of combustion in the previous engine cycle.