A dual-fuel engine system for a work vehicle includes an engine with a piston-cylinder arrangement defining a combustion chamber and an engine control unit (ECU). The ECU has a processing and memory architecture configured to execute instructions to deliver to the engine only a first fuel when an operating load of the engine is less than 5 a first predetermined threshold, deliver only a second fuel and operate the engine stoichiometrically when the operating load is greater than a second predetermined threshold. The second predetermined threshold is greater than the first predetermined threshold.

A flex fuel vehicle includes an engine that operates by burning an alcohol-containing fuel that is a mixture of alcohol and fuel produced from petroleum at any ratio. The flex fuel vehicle transmits an index indicating the concentration of alcohol contained in the alcohol-containing fuel being used to an external equipment outside the flex fuel vehicle.

A dual fuel system includes a first fuel supply of a first fuel, a second fuel supply of a second fuel, and a variable-output fuel pump. A fuel injector in the dual fuel system includes a combined-fuel outlet passage, a nozzle check movable to open and close the combined-fuel outlet passage to nozzle outlets, and a check valve positioned at least partially in a first fuel passage connected to the first fuel supply by way of the variable-output fuel pump. The first fuel may include a compression-ignition fuel and the second fuel may include an alcohol fuel. Varying output of the fuel pump during an off-cycle of a cam actuating a plunger in the fuel injector meters the first fuel to the fuel injector for forming a fuel charge for injection. Related apparatus and methodology is also disclosed.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

A dual fuel system includes a fuel injector having a fuel pressurization plunger, and a fueling control unit structured to determine a fuel bulk modulus term based upon a volume change value (dV) and a pressure change value (dP) for a fuel pressurized in the fuel injector. The fueling control unit is further structured to determine fuel injector control commands by way of map lookups on fueling maps selected on the basis of the fuel bulk modulus term. Related apparatus and methodology are also disclosed.

A dual fuel system includes a fuel injector having a fuel pressurization plunger, and a fueling control unit structured to determine a fuel bulk modulus term based upon a volume change value (dV) and a pressure change value (dP) for a fuel pressurized in the fuel injector. The fueling control unit is further structured to determine fuel injector control commands by way of map lookups on fueling maps selected on the basis of the fuel bulk modulus term. Related apparatus and methodology are also disclosed.

A system for handling surplus methane in a fuel supply system for an internal combustion engine (ICE) system, the system comprising: an inert gas supply system configured to be in fluid communication with the fuel supply system and further configured to supply inert gas to an inert gas supply conduit position of the fuel supply system; a burner configured to be in fluid communication with the fuel supply system via a controllable valve device, the controllable valve device being disposed downstream the fuel supply conduit position; and a controller comprising processing circuitry configured to: predict an upcoming ICE non-operational time period; in response to the predicted ICE non-operational time period, determine to inject inert gas to the inert gas supply conduit position so as to flush the fuel supply system; and control the controllable valve device to direct any flushed-out methane to the burner.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

In one instance, disclosed herein is a fuel-powered charging system, comprising: an engine-generator set comprising: an engine operative to combust a fuel to generate mechanical energy; a fuel injector operative to inject the fuel into the engine; a doser operative to dose the fuel with an additive to increase a reactivity of the fuel; and a generator operative to convert the mechanical energy generated by the combustion of the fuel within the engine into a first electrical energy; a battery operative to output a second electrical energy; and at least one charger operative to charge the battery using the first electrical energy. In another instance, engine operating methodology includes forming an engine starting charge of a dosed fuel based on selectively shutting down an engine, such as for cold starting the engine.