Dual fuel operating strategy for engine based on expected in-cylinder temperature progression

An engine system comprising:

• an engine including therein a combustion cylinder, and an intake port extending to the combustion cylinder;
• a fuel system including a first fuel supply of a first fuel, a first fuel injector fluidly connected to the first fuel supply, a second fuel supply of a second fuel, a second fuel injector fluidly connected to the second fuel supply, and a fueling control unit;
• the fueling control unit being structured to:
• output a first fueling command to the first fuel injector to inject the first fuel into a stream of pressurized intake air fed through the intake port;
• output a second fueling command to the second fuel injector to inject the second fuel directly into the combustion cylinder;
• and
• determine, via the first fueling command, at least one of an injection amount or an injection duration of the first fuel based on an expected progression of in-cylinder temperature in an engine cycle from an autoignition temperature of the first fuel to an ignition temperature of the second fuel.

A fuel system for an engine system comprising:

• a fueling control unit structured to:
• output a first fueling command to a first fuel injector at a first injection location of the engine system to inject a first fuel into a stream of pressurized intake air fed through an intake port to a combustion cylinder;
• output a second fueling command to a second fuel injector at a second injection location of the engine system to inject a second fuel into a mixture of the pressurized intake air and the first fuel in the combustion cylinder;
• and
• determine, via the first fueling command, at least one of an injection amount or an injection duration of the first fuel based on an expected progression of in-cylinder temperature from an autoignition temperature of the first fuel to an ignition temperature of the second fuel.